LAST EDITED ON 07-03-13 AT 04:14 PM (EST)Still no real idea on who the killer is...
If there are any clues in the manner in which the murders were planned, the means the killer has at his/her disposal, my chief suspect would be Lindsey. She's an engineer.
In murdering Sheri the killer was somehow, without spending very much time at it, able to remove one pane of glass from a multi-pane window, apparently without breaking the glass which would have made some noise and left behind broken glass.
In murdering Dontae the killer was somehow able to get ahold of benzene, not something you can just buy off the shelf, a very strictly regulated substance. But it is an ingredient in some manufactured products, and has useful applications in chemical processing and electrical engineering.