That was the entire clans excuse for camping the entire match. Me and my team of randoms stood no chance against their very well done camping (assault shields, trophy systems, etc). I couldn't get past their defenses. Just thought I would pointlessly share my COD Black Ops II experience.
Nothings right with you if nothings wrong with you.
Were they camping in a room? If they're upstairs, throw an EMP grenade into the floor below. If they're on the ground floor, throw the EMP grenade at the base of the wall. It should take out all the equipment. Camping is extremely easy to counter.