a couple things
when a few individuals would kill us, we only got their name in the middle of our screen, no killed by or a weapon, just the name.
Thats not so much our reasoning, the bigger thing was that they were able to shoot us without being able to see us, for instance on Desert Shield. we were getting hit, and killed, by a single RPG, fired from the East Base while we were still driving past the south base. On lost village i know they were using the exploits there, but because we won that round we are unable to do much about it.
The match was played on their server, but this clan has gotten caught for cheating before, which is our main reason for believing they are cheating.