So, I got fed up with waiting for the owner to reset the server. I ended up moving the old discourse to another folder, as you mentioned in the post to move to a new folder called “discourse-bad”.
I then simply followed the discourse installation instructions step by step. Entered the info from the old app.yml file into the new one. Moved the backup .tar file from the old directory into the new directory and then followed the instructions here to restore from backup. We are now back online!
Is there anything I need to do from here with pushing the git repo? I want to make sure that it doesn’t screw up again.
Edit: adding to this solution that the Ubuntu version was step upgraded from 18.04–>20.04–>22.04. Not sure if this contributed to the success but I would say it was an important step anyway.