Yeah I really need to find out if CP left the door locked or unlocked when he left in the morning. That should give us some answers...
Again, it means NOTHING because regardless of whether it was left locked or unlocked, Kortne was not the person who did it. So that won't give us any answers.
Here are some scenarios to make it clear because it seems that it's a little difficult to understand.
K and guest are in the apartment, she locks the door. Something happens to K. Guest takes her out of apartment to "hide" her to keep from getting in trouble.
another one...
K and guest are in apartment sleeping. Door is left unlocked. Someone comes in, takes K out of apartment and takes her to unknown place. Guest wakes up, leaves (locks door or leaves unlocked).
another one...
K and guest are in apartment. K goes outside and leaves door unlocked. Something happens outside. Guest wakes up, leaves (locks door or leaves unlocked).
I'm not trying to sound rude, but I really do think we're consuming way too much time trying to figure out if the door was left locked or unlocked. Regardless of the scenario, when her mom came to the house Monday, the door was locked or unlocked because of the guest or if/when K and guest left the apartment to go elsewhere.