NVidia bookworm repo worked fine on all my machines. What did not work for you? I deduced there wasn't really anything Debian-12 specific in there (it's still a Linux kernel with SystemD).
Realistically I can live on X11 outside of my dual monitor setup and that one application, but things get very choppy with mixed refresh rates. Still not the biggest fan of Gnome, but if I'm using deskflow only Gnome or KDE support the input sharing portal on Wayland.