I'm good with scifi
Wouldn't mind being a fallen ship mechanic- there are always someone needed to fix stuff, even if it's fixing the stuff that fixes everything. Like... someone who knows people wouldn't react well to realize that their entire world was actually fake, so he keeps his silence as they work it out, fearing that they might run out of time, you know? The hull would be massively strong, to support a failure such as the majority of the population just disappearing, and the deterioration accompanying the lack of mechanics and the like to keep the ship going. After all, it'll only take one tiny, itsybitsy little hole for the entire ecosphere to die- that hole will be air>vacuum, and the vacuum would be pulling the air out so hard that it'd likely tear half the hull apart.