Hmm, did you or your friends kept going in the teleporter and out? You know how you turn on pack a punch and you can keep going through the teleporter without waiting it to cool down or whatever.
this happened to me and some friends once and we didnt go into a teleporter, we were up in the war room also.... i think it has something to do with treyarchs servers lagging but idk this happened to us 4 or 5 times in a row and we had to keep restarting cuz we couldn't aim at him