Nice list, Bob. Intresting to note these old United Artist-related presences (probably the three War quads arent' here because they own the masters and have it licensed to Avenue rec.; why no Shirley Bassey?).
Here's the status of the release regarding these titles:
Byrd, Donald – Black Byrd (Quad 8 track only)
Byrd, Donald – Street Lady (Quad 8 track only)
Fiddler On The Roof – Film Soundtrack (Double Quad 8 track only)
Gentle Giant – Time To Kill (unreleased?) (Really unreleased and afaik never rumored about it)
Jethro Tull – MU Best Of (unreleased) (Really unreleased and IIRC it had a cd4 cat. n. assigned)
Jethro Tull – Warchild (Released on quad reel, cd4, 8 track)
Jethro Tull – Minstrel In The Gallery (UK – unreleased) (same as MU)
Jethro Tull – Aqualung (UK) (Released on quad reel, cd4, 8 track)
Lennon, John – Walls And Bridges (Quad 8 track only)
Live And Let Die – Film Soundtrack (Quad 8 track only)
McCartney, Paul – Band On The Run (Quad 8 track + DTS CD by HDS)
McCartney, Paul – Venus And Mars (Quad 8 track + DTS CD by HDS)
Miller, Steve – Fly Like An Eagle (Quad 8 track + DD DVD on the 30th anniv. edition)
Miller, Steve – Live (Really unreleased and afaik never rumored about it)
Pink Floyd – Dark Side Of The Moon and Pink Floyd – Atom Heart Mother (UK): (there's an encyclopedia to write about it... in short: nuke the Usa quad "master tapes" and get the true UK ones. Long reply: see here:
https://www.quadraphonicquad.com/QQ-PFQ.htm )
Ventures, The – Only Hits (Quad 8 track only)
Venutres, The – Hawaii Five-O (Quad 8 track only)
Womack, Bobby – Looking For Love Again (Quad 8 track only)
Womack, Bobby – Facts Of Life (Quad 8 track only)
Chances of a release of the quad mix for DSOTM is next to zero, since PF did remixed it in 5.1 for the sacd release; however, this would be for sure a long seller.
Shouldn't be there also the quad master for John Lennon "Imagine" and Ringo Starr "Goodnight Vienna"? Both released in USA as Quad 8 track.