it seems to me by the video that the elevators conveniently stop working when she gets on. the EXACT moment when she wants nothing more in life than to flee this place. And what a big coincidence this SAME girl is found in the water tank of the hotel? no matter what time-line of events you can conceive, and my guess is the possibilities are all over the place, it is MY opinion she was targeted and someone with the know-how did this. If you have made the decision in your heart that it is some how okay to kill someone, because that's where the decision lies, You don't just suddenly say hey I'm going to kill someone in a hotel, fuck with the elevators and then throw her naked lifeless body in a water tank. there has to be an established plan of action, then you find the target