[@Majoras End][@Mateotis][@FamishedPants]

Seems I made this one a bit harder than I intended, so here's a few hints. They get gradually stronger, and I'd rather you only look if you're super stumped.

[hider=Barely a hint]

For the moment, ignore the possibility of Emily using Jez's handbook to open the door. The goal here is to fine an alternate way the door could have been opened.

[hider=Tiny hint]

The tape on the bottom of the door was intended to hold [i]something[/i]. It's up to you to find out what that is.

[hider= Medium sized hint]

If the killer knocked out Jez, they probably had her handbook for a time. Could they have set something up from inside her room?

[hider=YET ANOTHER Medium sized hint]

Locked or not, the door can always be opened from the inside. If what Emily says is true, there was nobody inside the room aside from an unconscious Jez. Whatever was taped to the bottom of the door helped the killer access the room from the outside. 

[hider=Pretty big hint, practically gives it away NGL]

What was the murder weapon?
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