I think they are just 4 people that like realtimes together.
if you examind the game you linked to at all, you would have seen that all of their moves are really close together.
2007-01-05
10:37:03 - RiskTycoon fortified 34-Down with 1 armies from 41-Across
2007-01-05
10:37:13 - pELZYPELZ receives 4 armies for 12 territories
a ten second change would be hard to switch between players, even with multiple browsers open (if only one person is contrling them)
and they dont seem to be favoring eachother
I say NOT MULTI