Upon further investigation, mine don’t exactly match anywhere (TVDB, TMDB or watch.plex). There seems to be some kind of ‘glitch’ in my Plex server/metadata with the thumbnails. I’ve tried removing the entire The Love Boat folder, doing the Plex Dance, and moving the folder back but the thumbnails are still wrong. You can see here screenshots for two of episodes in season 5. TMDB and watch.plex are correct but mine are not - they appear for different episodes.
TMDB:
watch.plex:
my PMS:
