gui working while the local console looks stuck is usually getty or fb after the kvm got plugged in for me.
from ssh or the web shell:
-systemctl status getty@tty1 getty@tty2
-journalctl -b -u getty@tty1 --no-pager | tail -40
-Ctrl+Alt+F2 then F3 on the kvm and see if another tty answers
-midclt call system.general.config
if tty2/3 work, just leave the kvm on that one. if all ttys blank, drm with that kvm edid can do it. boot once with nomodeset or swap cable/port to test.