We replaced the banged-up magnet, the shorted coil, and rebuilt the moon driver board.
Then we replaced a bunch of stuff on the control board, which might have ended up being unnecessary. Why? Because we had the wrong transistor on the moon aux driver board!
We used an IRF540 transistor, instead of the proper replacement IRL540.
Huge thanks to Ottawa tech Sylvain for spotting our problem.
Either way, here it is in glorious action.
All that remains is fitting a new plastic above the moon standups so that the ball doesn't get stuck in there. I had tried re-glueing and reinforcing the broken old plastic, but that lasted less than a day with the ball getting whipped at it.