I may have solved my problem. After deleting the domain from the domainlist xml file AND relocating the domains folder, I was able to add the domain again. When I copied the old folder back, it would disappear again. I was able to use a backup (Thank you Datto Alto!) and restore that folder from an hour prior to the issues. I was also able to utilize the current User folder in the original file so that no one lost any emails (hopefully). Hopefully this makes sense. It is working!
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