If the clone's muscles have been electrically stimulated whilst it grows, you could imagine a small device at the base of the brain stem that records which signals produce which physical responses.

If a similar device on the brain stem of the brain donor maps out their signal-response relationships, you could presumably build a translation layer that sits between the donor brain and clone body.

I agree that this probably wouldn't work though. This is more like science fiction than a serious suggestion.

Yeah, it's a lot of if's and billions of dollars for what MIGHT be a free lunch when it comes to organ replacements.

Seems like a smarter idea would be to spend that money on growing organs in a tank. There are tens or hundreds of millions of otherwise healthy people in need of a donor kidney or two, and if the body didn't reject them in the process that would be platinum sprinkles on a gold sandwich.