ISO after Backup won't load -> "Mademoiselle (1966)" 2023 DVD reissue

[Sutrosonics]

I've run into issues where the backup fails during the creation of an ISO but never this specific issue.

It gives absolutely no indication that the backup failed. Chugs along happily and tells me that it completely successfully. However, when I open the ISO and try to play it on my Mac in "DVD Player," I only get a black screen. Click on menu -> "NOT PERMITTED" Nothing more than that. I'm at a loss since it literally gave me zero errors during the backup process. Same result backing up with two different release of MakeMKV. I understand the movie is a little esoteric. It's a classic foreign french film. Kinda doubt anyone else has tried to back this one up. Still. Any clues?

MacOSX 10.14.6 minimac 5,2 MakeMKV (1.18.4 & 1.20.0)

Thanks!