Knowing you have about 12-15hours left. And the owner of the company is on board.

I mean even if they find it NOW, is that even enough time to bring it up? The whole process with depressurization is quite slow, they would have to get oxygen supply down there. Not even talking about the means required to get down there.

Edit: The failsaves should have apprently brought it up to the surface. Even if the crew is passed out.