"I assume these two players are friends or family members"
This is the only correct statement.
There have been some games, actually, a lot, recently, where there would be one deadbeat, so technically a 2/4 expectancy isn't even correct.
In one of the games you provided (
https://www.conquerclub.com/game.php?game=19796059 )
2020-03-31 17:53:04 - EEEE4 eliminated DeathCoil from the game
2020-04-01 12:01:38 - Sleeping_Beauty: So, you guys are definetely plotting against me hahha
2020-04-01 12:06:16 - Sleeping_Beauty: No way green is that bad
2020-04-01 12:07:30 - Sleeping_Beauty: How come none never report on you before?
This was yellow talking to green/blue. I was already eliminated at that point. Ironically, by EEEE4. I actually didn't even realise I/we played against this player twice.
Bigger log:
2020-03-31 17:53:04 - EEEE4 eliminated DeathCoil from the game
2020-03-31 17:53:31 - EEEE4 assaulted Magadan from Yakutsk and conquered it from Sleeping_Beauty
2020-03-31 17:54:33 - EEEE4 assaulted Dakar from Sao Paulo and conquered it from Sleeping_Beauty
2020-03-31 17:55:01 - EEEE4 ended the turn and got spoils
2020-03-31 19:28:58 - bermanap received 2 troops for holding Oceania
2020-03-31 19:28:58 - bermanap received 4 troops for 13 regions
2020-03-31 19:29:05 - bermanap played a set of Perth, Bangkok, and Tokyo worth 6 troops
2020-03-31 19:29:05 - bermanap got bonus of 2 troops added to Perth
2020-03-31 19:29:05 - bermanap got bonus of 2 troops added to Bangkok
2020-03-31 19:29:31 - bermanap deployed 12 troops on Vancouver
2020-03-31 19:29:33 - bermanap assaulted Anchorage from Vancouver and conquered it from Sleeping_Beauty
2020-03-31 19:29:44 - bermanap reinforced Mexico City with 6 troops from Anchorage
2020-03-31 19:29:44 - bermanap ended the turn and got spoils
2020-04-01 03:04:17 - Sleeping_Beauty received 3 troops for 7 regions
2020-04-01 03:04:20 - Sleeping_Beauty deployed 3 troops on Dubai
2020-04-01 03:04:26 - Sleeping_Beauty assaulted Delhi from Dubai and conquered it from EEEE4
2020-04-01 03:07:32 - Sleeping_Beauty ended the turn and got spoils
2020-04-01 03:07:32 - Incrementing game to round 9
2020-04-01 06:16:53 - EEEE4 received 2 troops for holding South America
2020-04-01 06:16:53 - EEEE4 received 6 troops for 19 regions
2020-04-01 06:16:59 - EEEE4 deployed 4 troops on London
2020-04-01 06:17:01 - EEEE4 deployed 4 troops on Dakar
2020-04-01 06:17:06 - EEEE4 assaulted Mexico City from Bogota and conquered it from bermanap
2020-04-01 06:17:25 - EEEE4 reinforced Hong Kong with 19 troops from Dakar
2020-04-01 06:17:25 - EEEE4 ended the turn and got spoils
2020-04-01 07:34:55 - bermanap received 2 troops for holding Oceania
2020-04-01 07:34:55 - bermanap received 4 troops for 13 regions
2020-04-01 07:35:07 - bermanap deployed 6 troops on Bangkok
2020-04-01 07:35:23 - bermanap assaulted Magadan from Anchorage and conquered it from EEEE4
2020-04-01 07:35:33 - bermanap reinforced Bangkok with 2 troops from Perth
2020-04-01 07:35:33 - bermanap ended the turn and got spoils
2020-04-01 08:00:48 - Sleeping_Beauty received 3 troops for 8 regions
2020-04-01 08:01:02 - Sleeping_Beauty played a set of New York, Dakar, and Jakarta worth 8 troops
2020-04-01 08:01:13 - Sleeping_Beauty deployed 11 troops on Cairo
2020-04-01 08:01:18 - Sleeping_Beauty assaulted Dakar from Cairo and conquered it from EEEE4
2020-04-01 08:01:38 - Sleeping_Beauty assaulted Sao Paulo from Dakar and conquered it from EEEE4
2020-04-01 08:02:50 - Sleeping_Beauty assaulted Istanbul from Dubai and conquered it from EEEE4
2020-04-01 08:04:12 - Sleeping_Beauty reinforced Cairo with 3 troops from Dakar
2020-04-01 08:04:12 - Sleeping_Beauty ended the turn and got spoils
2020-04-01 08:04:12 - Incrementing game to round 10
2020-04-01 08:59:22 - EEEE4 received 5 troops for 16 regions
2020-04-01 08:59:26 - EEEE4 played a set of Bogota, Buenos Aires, and Montreal worth 10 troops
2020-04-01 08:59:26 - EEEE4 got bonus of 2 troops added to Bogota
2020-04-01 08:59:26 - EEEE4 got bonus of 2 troops added to Buenos Aires
2020-04-01 09:00:04 - EEEE4 deployed 15 troops on Buenos Aires
2020-04-01 09:00:08 - EEEE4 assaulted Sao Paulo from Buenos Aires and conquered it from Sleeping_Beauty
2020-04-01 09:00:41 - EEEE4 reinforced Sao Paulo with 2 troops from Bogota
2020-04-01 09:00:41 - EEEE4 ended the turn and got spoils
2020-04-01 09:04:37 - bermanap received 2 troops for holding Oceania
2020-04-01 09:04:37 - bermanap received 4 troops for 14 regions
2020-04-01 09:04:47 - bermanap deployed 6 troops on Havana
2020-04-01 09:04:50 - bermanap assaulted Mexico City from Havana and conquered it from EEEE4
2020-04-01 09:05:00 - bermanap reinforced Mexico City with 2 troops from Montreal
2020-04-01 09:05:00 - bermanap ended the turn and got spoils
2020-04-01 10:15:40 - Sleeping_Beauty received 3 troops for holding Africa
2020-04-01 10:15:40 - Sleeping_Beauty received 3 troops for 10 regions
2020-04-01 10:16:02 - Sleeping_Beauty deployed 6 troops on Dakar
2020-04-01 10:16:12 - Sleeping_Beauty assaulted Madrid from Dakar and conquered it from EEEE4
2020-04-01 10:16:37 - Sleeping_Beauty ended the turn and got spoils
2020-04-01 10:16:37 - Incrementing game to round 11
2020-04-01 10:32:41 - EEEE4 received 2 troops for holding South America
2020-04-01 10:32:41 - EEEE4 received 5 troops for 15 regions
2020-04-01 10:32:56 - EEEE4 deployed 7 troops on Hong Kong
2020-04-01 10:33:01 - EEEE4 assaulted Delhi from Hong Kong and conquered it from Sleeping_Beauty
2020-04-01 10:33:11 - EEEE4 ended the turn and got spoils
2020-04-01 10:52:10 - bermanap received 5 troops for holding North America
2020-04-01 10:52:10 - bermanap received 2 troops for holding Oceania
2020-04-01 10:52:10 - bermanap received 5 troops for 15 regions
2020-04-01 10:52:25 - bermanap deployed 4 troops on Bangkok
2020-04-01 10:52:32 - bermanap deployed 4 troops on Anchorage
2020-04-01 10:52:38 - bermanap deployed 4 troops on Montreal
2020-04-01 10:52:40 - bermanap assaulted Reykjavik from Montreal and conquered it from Sleeping_Beauty
2020-04-01 10:53:00 - bermanap ended the turn and got spoils
2020-04-01 11:01:53 - Sleeping_Beauty received 3 troops for holding Africa
2020-04-01 11:01:53 - Sleeping_Beauty received 3 troops for 9 regions
2020-04-01 11:02:32 - Sleeping_Beauty deployed 2 troops on Dubai
2020-04-01 11:02:41 - Sleeping_Beauty deployed 4 troops on Istanbul
2020-04-01 11:02:44 - Sleeping_Beauty assaulted Berlin from Istanbul and conquered it from EEEE4
2020-04-01 11:03:05 - Sleeping_Beauty reinforced Dakar with 2 troops from Istanbul
2020-04-01 11:03:05 - Sleeping_Beauty ended the turn and got spoils
2020-04-01 11:03:05 - Incrementing game to round 12
2020-04-01 11:10:18 - EEEE4 received 2 troops for holding South America
2020-04-01 11:10:18 - EEEE4 received 5 troops for 15 regions
2020-04-01 11:10:27 - EEEE4 played a set of Lagos, Sydney, and Perth worth 8 troops
2020-04-01 11:10:35 - EEEE4 deployed 15 troops on Tokyo
2020-04-01 11:10:38 - EEEE4 assaulted Magadan from Tokyo and conquered it from bermanap
2020-04-01 11:10:48 - EEEE4 reinforced Hong Kong with 14 troops from Tokyo
2020-04-01 11:10:48 - EEEE4 ended the turn and got spoils
2020-04-01 11:19:39 - bermanap received 5 troops for holding North America
2020-04-01 11:19:39 - bermanap received 2 troops for holding Oceania
2020-04-01 11:19:39 - bermanap received 5 troops for 15 regions
2020-04-01 11:19:45 - bermanap played a set of Nairobi, New York, and Magadan worth 8 troops
2020-04-01 11:19:45 - bermanap got bonus of 2 troops added to New York
2020-04-01 11:19:54 - bermanap deployed 20 troops on Bangkok
2020-04-01 11:20:05 - bermanap assaulted Hong Kong from Bangkok and conquered it from EEEE4
2020-04-01 11:20:36 - bermanap ended the turn and got spoils
2020-04-01 11:24:59 - Sleeping_Beauty received 3 troops for holding Africa
2020-04-01 11:24:59 - Sleeping_Beauty received 3 troops for 10 regions
2020-04-01 11:25:11 - Sleeping_Beauty played a set of Cape Town, Cairo, and Mexico City worth 6 troops
2020-04-01 11:25:11 - Sleeping_Beauty got bonus of 2 troops added to Cape Town
2020-04-01 11:25:11 - Sleeping_Beauty got bonus of 2 troops added to Cairo
2020-04-01 11:25:32 - Sleeping_Beauty deployed 2 troops on Dakar
2020-04-01 11:25:39 - Sleeping_Beauty deployed 3 troops on Dubai
2020-04-01 11:26:13 - Sleeping_Beauty deployed 2 troops on Dubai
2020-04-01 11:26:27 - Sleeping_Beauty deployed 5 troops on Istanbul
2020-04-01 11:27:00 - Sleeping_Beauty assaulted Moscow from Istanbul and conquered it from EEEE4
2020-04-01 11:28:48 - Sleeping_Beauty reinforced Dubai with 2 troops from Cape Town
2020-04-01 11:28:48 - Sleeping_Beauty ended the turn and got spoils
2020-04-01 11:28:48 - Incrementing game to round 13
2020-04-01 11:31:08 - EEEE4 received 2 troops for holding South America
2020-04-01 11:31:08 - EEEE4 received 4 troops for 14 regions
2020-04-01 11:31:11 - EEEE4 deployed 6 troops on London
2020-04-01 11:31:12 - EEEE4 assaulted Madrid from London and conquered it from Sleeping_Beauty
2020-04-01 11:31:23 - EEEE4 assaulted Dakar from Sao Paulo and conquered it from Sleeping_Beauty
2020-04-01 11:31:37 - EEEE4 ended the turn and got spoils
2020-04-01 11:43:40 - bermanap received 5 troops for holding North America
2020-04-01 11:43:40 - bermanap received 2 troops for holding Oceania
2020-04-01 11:43:40 - bermanap received 5 troops for 16 regions
2020-04-01 11:43:53 - bermanap played a set of Port Moresby, Johannesburg, and Anchorage worth 6 troops
2020-04-01 11:43:53 - bermanap got bonus of 2 troops added to Port Moresby
2020-04-01 11:43:53 - bermanap got bonus of 2 troops added to Anchorage
2020-04-01 11:43:56 - bermanap deployed 18 troops on Hong Kong
2020-04-01 11:44:01 - bermanap assaulted Delhi from Hong Kong and conquered it from EEEE4
2020-04-01 11:44:17 - bermanap assaulted Dubai from Delhi and conquered it from Sleeping_Beauty
2020-04-01 11:44:25 - bermanap assaulted Nairobi from Dubai and conquered it from Sleeping_Beauty
2020-04-01 11:44:34 - bermanap reinforced Mexico City with 2 troops from New York
2020-04-01 11:44:34 - bermanap ended the turn and got spoils
2020-04-01 12:03:25 - Sleeping_Beauty received 3 troops for 7 regions
I was already eliminated for several turns, but I guess teaming / diplomacy also applies from the grave.
Any agreements, diplomacy, whatever, when present, is always made in game chat. Often it is apparent that attacking one an other isn't a good move, same goes for with other players.