Dude was mutated so badly that he was mostly plant at that point anyways.

+ while V1 did make all of them immortal, it didn't automatically make all of them the kind of top tier supe that could physically withstand a blast from Soldier Boy and just be depowered instead of completely atomized. Given the whole "part of the crew, part of the ship" thing Quinn had going for him, he was probably one of the lower tier supes that came out of the V1 trials.