The main issue I need to fix right now is the database, I can't do anything with nodebb until the database is working properly.
But running that command will likely tell you why the application is not connecting to the DB...
The fix, once the cause is determined, will likely be easier than a fresh install
I can't even start the database on its own. A fresh install is very easy, would take under 30 minutes, and then if it is possible, I'm sure merging the old database isn't too hard.