I was using a flamethrower and I ran out of ammo, switched to pistol and went to a terminal and it said my flamethrower was full of ammo. I went to check, and sure enough, It was true.
Ok, I think I got all the endings:
Save at least one person
When the war starts, go back to the spaceship
Let everyone die adn then go back to the spaceship.
It sounds like a bug, but at least it's a good one.