Keyboard and mouse frozen, cannot log in, I don't think it's sys-usb though

[tzwcfq]

1. You can restore your EFI boot record by running this command from your Qubes ISO rescue terminal or from new Qubes on 2.5" SSD:
   Assuming /dev/nvme0n1 is your old Qubes drive and EFI partition number on this disk is 1.
   efibootmgr -v -c -u -L QubesOS -l /EFI/qubes/grubx64.efi -d /dev/nvme0n1 -p 1

2. You can try to boot your old Qubes with qubes.skip_autostart option:

Can't use keyboard or mouse after installing sys-usb

add qubes.skip_autostart to kernel option when you in grub menu, so your kernel paramenter have something like ............rhgb quiet qubes.skip_autostart then f10 to boot to modify kernel parameters, press e when you in grub menu.

3. I think you have a problem with vgchange in new Qubes if you try to mount it in dom0 since it’ll have the same default volume name qubes_dom0.