www.makemkv.com

On each disc, there is an episode that is offered with text commentary. This was implemented by creating two separate playlists, where one playlist has additional subtitle tracks for the commentary. (I determined this by playing back the disc using VLC.)

When I rip the disc, both playlists show up, but neither playlist contains the additional subtitle tracks.

If I make a backup of the disc and play the backup in VLC, the subtitles are there. Is there a way to browse the backup and retrieve the missing subtitles?

If you open the decrypted backup in MKVToolNix you might be able to see the missing subtitle track and include it in the .mkv file.