The option he tries to suggest, going back to the hangar, sounds safer than either leaving now or staying with Taro. We can presume there are also some more people from their own side at the hangar, so it would permit a chance of leaving the cockpit without encountering a bunch of hostiles at close range.
Baring that, getting caught with Taro in the cockpit still seems safer to me — but feel free to disagree. It doesn’t really matter because if we can’t agree which of those options is better, then the chances of our two professors to come to the “correct” conclusion with any certainty, while trying to deal with Taro, the Engine and the fact that they are a lot more likely to both be dead in a few minutes than anyone can be comfortable with, is pretty low. They see something that might look like a straw, they grab it.