If according to Kaylee's dad, his daughter was the alleged target of the killer, I can't help but wonder why the killer would plan the brutal attack on Sat evening, the most likely day that E (strong, male guest) would be present, knowing that he could attack any other day without the threat of encountering a big guy like E. This doesn't follow...
Instead, it definitely makes me ask whether or not E was the target of the psycho-killer. Logic indicates it is better to attack E in a house with three (or possibly five) petite women than his own frat house full of young men.
And if E was the target of the killer, I can also see the killer taking out the three women (collateral damage) that in the mind of the deranged killer -- could even be intended to publicly shame big E who by all accounts was a prince of a guy.
IMO, I think the killer is feeling very proud of himself and will not be able to resist bragging about his conquest.
There really is nobody better at this sort of profiling than the FBI and I don't doubt they are all over the sites they believe the killer is likely to visit.