scummvm 2.6.0 release candidate now has support for sanitarium ^^^
https://github.com/scummvm/scummvm/blob/master/NEWS.md
https://www.scummvm.org/downloads/#daily
at the bottom. testing required, they are looking for testers for the new version
ScummVM 2.6.0pre Release Candidate Build - Windows Installer (recommended) (89.8M .exe, last update: 2022-06-06, sha256)

installed the ""ScummVM 2.6.0pre Release Candidate Build - Windows Installer (recommended) (89.8M .exe, last update: 2022-06-07, sha256)" from there :
https://www.scummvm.org/downloads/#daily

Decided to install it in C:\ScummVM\ to avoid possible file permission problem with window 10 various security systems

Copied the whole Sanitarium folder from C:\GOG Games\ to C:\ScummVM\

In ScummVM i clicked on the Add Game button, pointed to C:\ScummVM\Sanitarium
And ...
"ScummVM could not find any games in the specified directory"

Wondering if i was doing something wrong, i copied the Ultima6 directory i had to C:\ScummVM\
And after Add Game and pointing to the Ultima6 directory it found the game without a problem.

But why isn't it detecting Sanitarium is rather puzzling

EDIT : found the problem, you need to point scummvm to C:\ScummVM\Sanitarium\Data\ not simply C:\ScummVM\Sanitarium\
And then it will find the game

Please report any bugs you encounter with release candidate ScummVM 2.6.0 to the ScummVM bug tracker. The following weeks are the official public testing phase for the upcoming release, and at least the most outstanding reported bugs will have high priority to get fixed:

Bug tracker:
https://bugs.scummvm.org

How to report a bug:
https://docs.scummvm.org/en/latest/help/report_bugs.html

On Arch Linux using the latest stable ScummVM release 2.5.1, I had to move all music and video files from Data/Music and Data/Vids to Data/. Then it seems to work fine.

How do I report a bug?

The game worked fine before, why do I need ScummVM? Especially when it doesn't work? You guys even made it harder to report a bug, so the reports wouldn't flood your mailbox.

If you can't do it, don't do it, ffs.
This is infuriating; why the fuck would I go through all the trouble to log in to your client if I want to stay the hell away from it. because it prevents me from playing a game that worked fine without it? I don't understand!!!