Oh, I have a CalDigit TS4 that is exhibiting the same issue with the 3rd display being detected as an unknown display. I made the edits as OP to hopefully fix it. OP has kernel 6.10, but mine was 6.9.12, Today Fedora 40 got 6.10.3 but still no happiness with the mod:
The CalDigit TS4 doesn’t have a power button to turn on the laptop. I also had a Dell WD22TB4 that exhibit the same behavior and has a power button, but I didn’t test the power button functionality while I had it.