Solved, Updating thread for others.
Database was corrupted. dropped to a shell and copied the last backup I had to com.plexapp.plugins.library.db, deleted the db-shm and db-wal files, and fired up Plex. It started up. Somehow the database got corrupted and it’s running fine now, but we’ll see what happens if the DB gets corrupted again. If it does, I’m going to try and follow the steps outlined here: Database Corruption
For reference, the DB in an Unraid Plex docker is held at /mnt/user/appdata/PlexMediaServer/Library/Application Support/Plex Media Server/Plug-in Support/Databases
