Like the title title says.

Because his corpse would be a skeleton by now

Like the above said, his corpse is more skeleton than anything else by now. It'd probably be comparable to possessing a brick. And it's not like their aren't plenty of better candidates for him to possess if need be.

Yes, but if he had thought of it sooner he could have walked around as if he wasn't dead.

@themanintheshoe: It still would have decomposed at the same speed I think. I don't think his possessing preserves the host body, as far as I know.

Doesn't the host have to be living for Deadman to possess their body?