The 8GB file has the backstroke audio track and subs too; you just have to select them.
I did upload the audio separately. Have a magnet link.
No clips are missing; it's all there.
I’ve combined all the clips from YouTube and Vimeo into a single audio track, re-synced the subs, and muxed it into HiDt’s 720p release.
Forum rules prevent me from posting direct links, but I think I’m allowed to tell you to search for “backstroke” on TPB. 😉