How do I restore rofi to the default config files

I assume you're talking about the order in which apps appear when you first launch rofi. That's in the cache file in ~/.cache as something like rofi3.druncache or rofi-3.druncache (or both). Delete (or rename) them and see if that addresses your issue.

If you truly mean the config file, it's in ~/.config/rofi. Delete or rename to see if it fixes your issue