The -featurette, etc naming does not work for TV shows.
You have to put it in a Season 00 or Specials folder.
It does not appear in TheTVDB.com listings for Westworld, so you’ll have to give it a false episode number.
See Naming TV Show Specials for details.
/TV Shows
/Westworld
/Season 00
/Westworld - s00e99.mkv
/Season 01
/Westworld - s01e01.mkv
