I just bought the scuba mask and swam down to the safe, but it was already unlocked and there is no AI module in sight. Did it just fall out or something?  Is there a way to get a new one without having made Kerfur Omega already, or is my save just messed up?

Close it, do the code thing and reopen it, it should be there.

Or if you have a hacksaw just saw it and it'll spawn alongside the metal scrap.

Ah, that's a good idea, thanks. I already solved it since posting by making a new save and using the mailbox, but that would've been easier.