Just tried refreshing metadata on the show and the record is still there
I’ve never used any .plexignore files, but I just double-checked just in case and there are none
I just did the first half of the Plex Dance (moved the show’s folder out of the library, emptied trash and cleaned bundles, but I haven’t moved the folder back into the library yet) and the record for the extra is still there 
Edit 1: I just kicked off a refresh all metadata for the whole TV library, see if that changes anything
Edit 2: Nope, the record is still there
