33% success rate sounds about right for me too, maybe even lower. Hell, I just wiped two threatening games in row.
I can´t even say, it´s really that much better with friends, because the games are going more or less the same for any group I am in...room 1 - 4 cleared mostly without significant troubles, then we wipe during the last room. If you run into pug group that manages to win, stick to them if possible! They will probably try to stick to you as well 
The misfortune of DAMP is, that really carrying others like it was possible in ME is practically not an option here. Which really kills me, because I would love to help others to pull through, but as it is, the best I can do atm is trying to hold my own.