If there was a month earlier, perhaps I'd agree with you that he did not have the capability to commit a murder. But more than two months have passed, and he has become more accustomed to the body he's in now.

[ He folds his arms. ]

If not his cane, then it was some other blunt object. It could have been the rock was used more than once.

Regarding the flight problem, he could have ducked out of sight and then flown to get to his room in a position where he was more out of sight.

They are 'friends', but unfortunately, I do not know if that is enough.

That said, who else do you believe is a better suspect than Bill? Surely, you have some ideas. I know you think things through well.