The PlexData creation error is not fatal to PMS starting.
In PMS 1.20.2, PlexData will no longer show any errors. Its usage will be completely optional (works if present - ignored if not present)
As for PMS not starting, may I please see the entire ZIP set?
Go into PlexData,
Click “Plex Media Server”
Right-Click “Logs” -> Compress (generates a ZIP file)
Upload the composite ZIP here.