I know the game (and the original 2011 version) had multiple endings but did they put any in the demo? What about if you stood there for 20 minutes like the narrator said?
Entire answer is in spoiler tag since there's no way to avoid it.
No If you stand there for 20 minutes (actually more like one minute) he will just suggest a tour of the facility. It also doesn't matter how long you play the 8 game. Nor whether or not you wait in the waiting room.
There are some dialogue differences, but only one ending.