At the time of your accusation on him it was round 4 and he had attacked you 3 times and the other 2 players once each.
Everyone was trying to get established as was he, he made a move on to you cause from the looks of it from my recreation of your game you were ahead at the time.
You calling him out in chat like you did put an instant target on your back and every attack he made on you after that could have made no tactical significance at all and been justified.
You need to be careful when you use chat, its a tool, and sometimes it can be another enemy. You gave him a reason to do nothing but go after you after you called him a cheat.
And for the record Conquer Stats show him and every other player attacking equally until the last rounds when eliminations start to take play. At that time Red attacked yellow more and then Blue attacked Red to get him out of the game and win.
Also their country flags are different and they have no other threads about them.
Either way a quick IP will be done, but with this and only one other game between the two I doubt you will pull of a Diplomacy charge unless something is found in
Game 4343442.
Best of Luck
King Sam