To be honest... I know very little about the history of the film or area. but if I remember correctly... wasn't The Amityville horror based on a story thought to be true... then later debunked? I am not 100% sure... but it is based where it supposedly happened... if I am not mistaken somewhere in/around New Jersey? but take this all as pure speculation/rumor as I am basing it all on my foggy memory of what I read years ago.
OK... First thing... you may notice I did not watch Exorcist 2... I will not watch Exorcist 2.... I do not own Exorcist 2.... As far as I am concerned Exorcist 2 does not exist!