Check your usage:
[~] # export PLEX_MEDIA_SERVER_APPLICATION_SUPPORT_DIR="/share/CACHEDEV1_DATA/.qpkg/PlexMediaServer/Library"
[~] # cd /share/CACHEDEV1_DATA/.qpkg/PlexMediaServer/
[/share/CACHEDEV1_DATA/.qpkg/PlexMediaServer] # ls
CrashUploader* Plex Commercial Skipper* Plex Media Scanner* Plex Script Host* Plex Transcoder*
lib/ Plex DLNA Server* Plex Media Server* plex.sh* Plex Tuner Service*
Library/ Plex Media Fingerprinter* Plex Relay* Plex SQLite* Resources/
[/share/CACHEDEV1_DATA/.qpkg/PlexMediaServer] # ./Plex\ Media\ Scanner --list
1: TV Shows
3: tv2
4: tv3
[/share/CACHEDEV1_DATA/.qpkg/PlexMediaServer] #