One guy bails early, before we failed the optional even. Never said why he was leaving or that he was leaving, just left. The four of us left pushed all the way through to the final room (failing the optional along the way, I guess a prisoner died), then one of the others suddenly said "I have to feed my dog, sorry" and left. Down to three.
We could possibly have done the consoles, but one guy kept falling in the plasma where we couldn't revive him without him dying again. And he didn't listen or follow us when I said we all needed to be in the same corner. Two of us went left. He went right and got killed by a tactical drone.
We tried maybe four times before we realized it wasn't going to work. They bailed first... I left last.
But the funny thing is, I didn't get a penalty. It told me I would, but I could queue up for anything I wanted, even Infected Ground.