I had the strangest dream last night regarding this case... and I don't necessarily believe "things come to you in dreams " etc but I just have to post this here.
I dreamt a 35-45 yr old man, blond hair, he looked a lot like the guy from "The Mentalist", wearing of all things....a 2 piece brown bear suit, like a mascot costume or working at a theme park, he was the abductor. It was somehow tied to William in my dream. I saw William with this man holding his bear paw hand. And also riding on a city bus, lots and lots of bus rides in my dream.
I woke up thinking that maybe somehow William was enticed by a costume or something silly/funny and he was transported on the city bus line or across country.
Now I realize this is a silly dream, but I would never forgive myself if I didn't just write it down on this site and just put it out there.