@lister-of-smeg I was halfway through another process on resolving the issue when I saw this post, so I didn't get a chance to try it myself. I appreciate your help and the knowledge you shared though!
This whole mess was a lesson learned for me, so I'm on the same page with backing files up now. Copying that RetroPie-Setup folder was my first priority before running git reset --hard. Thankfully, it doesn't seem like anything broke.