Not sure if this is helpful, but this sounds a bit like my bug
The problem appears to be in DP / USB-C(?) daisy-chaining which it sounds like is what you’re doing. My bug didn’t get any traction, and I’m still using my workaround of just not daisy chaining.
The flash to black thing in your video is precisely what I would see. However, none of my monitors would get screwed up frames. I haven’t retested the newer drivers since I report my bug, but from your report it sounds like nothing has been fixed.