I am in the same situation as @vhaelan.
same as in same iGPU (alderlake) passed-through, same output for those latest commands, same OS (Fedora CoreOS on latest Xcp-Ng stable).
Tried current avenues suggested in this thread with no progress.

It seems vhaelan has settled with CoreOS under Proxmox (which works!). He also mentioned it works in Debian under XCP-ng, though I haven't tested that myself.

I would appreciate additional suggestions for troubleshooting to take this further, in case anyone has any other ideas.