The witch coerced the victim into opening the door, entered the room, set a trap while the victim was distracted, left the room, and the victim locked the door before triggering the trap.
The witch set a trap after I had already left.
The victim was actually moving in and hadn't finished organizing his things; then, he accidently cut himself trying to prepare food. After seeing and blood, he suffered a heart attack putting him into cardiac arrest. With his heart no longer able to function, he was clinically dead. He laid unconscious on the ground from blood loss; then, upon entering the room, it appeared as if he was fully dead. The staff member who opened the door then used a knife to stab him and kill him instantly.
The witch staged an event outside the victim's window to distract the victim. Then, while the victim was distracted, the witch unhinged the door and entered the room. The witch then killed the victim, left the room and re-hinged the door.
As the victim leaned out one of the windows, the witch stuck their legs in through the window, not being able to fit all the way because a human can't but being able to place their legs in (technically making them inside). Then, the witch shot the victim who fell back through the window and the witch withdrew all appendages from the window and left.