Now that the patch is up, here's what I had to do to get my scores back to normal.

1. Delete your Player Profile save data. You'll lose your stars and experience, but high scores and trophies remain.

2. Play your tables - after your game is over, no matter how well you did that game, the HIGHEST score you've reached on the LEADERBOARDS will be set as your high score for that table/mode. So that's atleast some good news!

3. Go into the leaderboards, and look at your wizard score - after I finished playing a table, I had normal wizard and super scores, but on the main menu it was still set to over 8 billion. After I looked at it, it went back to normal.

Hopefully the patch really did fix everything, and after doing all this my scores don't go wonky again, but so far it seems to be working!