I'd like to believe that the police really did investigate him and continue to keep an eye on him. It seems to me that police rarely admit when a suspect is truly a suspect. Maybe it lulls a suspect into a false sense of security? Seems a little silly to me but, hey, what do I know?
Regarding Manorville, I would think that the killer would have to have some tie to the area in order to feel comfortable dumping there. Not that I would ever do such a thing but, if I did, I certainly would make sure that I knew the place well. (Wow, that sounds so creepy. Don't judge me, people!)
And, yeah, I agree... so much info about the doctor and hardly anything on the john! It doesn't make sense.