I feel your pain. Mine works perfectly now and that's with the latest version of firmware and UC driver. So persist is my advice.
Make sure you completely uninstall your current version of the UC driver. I used Clean My Mac but i think there is an uninstaller in the UC package.
After uninstall i went back to an older version of the UC driver (March 2021) and installed that. Then the mac sees the Quantum. As stated I later installed the very latest version of the UC driver and the Quantum firmware and all is good.