I’m not sure about the why or what causes the combination of Qubes OS + Lenovo laptop + AMD CPU/GPU causes that many problems. :-/
I suspect it’s something with Xen - I did try to install Xen while my T14 had a xUbuntu installed … and as I recall, that also failed to start … :-/
Adding to my issues, the WLAN card in my machine should be a “Qualcomm Wi-Fi 6E NFA725A 2x2 AX” (based on the Lenovo information) and it looks to have problems as well: Installation of Qubes on ThinkPad T16 - #44 by apparatus :-/