(Spoilers ahead!)
V3 of the Beta, (microchip scene done, ship built and fuelled) in the Two Guys' dome computer room, Ace is trapped after the Chuck Yegger game (which I skipped after night 1). I'm in control of Rooter but don't seem to be able to do anything to get Ace out. Narrator mentions getting the Two Guys for help, but they're gone when you return to the upper dome area.