I've read other threads concerning the game and there's been mention about a grenade which will allow you to see a third ending. I've played the game through, but I have no idea where this grenade is. I'm assuming it's on the ice planet.
Hello? Anyone?
Spoiler
in the room with teleporter on icy planet there are some crates on the right. If I remember right, you have to use the kfife with those crates. Then you will see an hole in a crate. Look&Interactwith this hole and you get a granade.