Actually, Schiavo handed out three extra apartment keys -- one to Ted Bundy, one to O.J. Simpson and one to a shadowy figure named "Tookie." Does this help your theory that Mikey didn't do it?
Michael would not want to be seen standing in the way of people trying to determine what really happened to Terri. Michael can't object to a little bit of investigation, if the investigators are trying to find out if his "beloved" Terri was harmed by other humans.
Michael and his cohorts insist he didn't do anything to Terri, so why not start there and ask if anyone might have harmed Terri?
I'm not saying Michael isn't involved. I'm saying that a few "outside of the box" questions might shake up the stalemate.