@AndyHen
Several months ago I moved my GC-Titan Ridge AIC from my Designare Z390 to my Z690 Aero G running Monterey. On the Aero G thread someone had asked about using the Apple TB display with it. I brought the display out of storage and connected it to the Titan Ridge card, and it worked well as a dual display.
So changing motherboards and macOS versions didn't prevent the Apple TB Display from running for me. I don't use dual displays so the display is now back in storage.
I suspect it is a mater of tweaking something. With
@CaseySJ on your case, I suspect the problem can be identified and corrected. Good luck.