The Captain wrote:Doesn't matter if the O2 is fixed if you don't power it. Maybe an Engi/Zoltan hybrid would do the trick.
While the unpowered O2 was what killed him, what put him in the state where he was ready to die from a puff of smoke was when he fixed the air-free O2 room a few fights earlier. An Engi would have helped fix that up a lot quicker than a Mantis.