Yes that update where grub2 script runs now shows you with normal looking out put for both kernels so you should have boot entries for both in /boot/grub2/grub.cfg and you should be able to boot to both kernels. So this problem is fixed.
Note about your repositories. Normally people just use the main, unsupported, restricted, non-free and the update repos for those 4. All that debug stuff is for developers and is not hardly used in Rock/Lx 4.1. My Rock systems all look like this screen shot:
Also so you and other users know the restricted repos that return 404 Cannot download error don’t have any packages in them. So they are empty and dnf does not have a metadata file to find so it will list those as 404 Cannot download. No worries for those.
@aus9 in view of some of the weird things we have seen with your system you could try to disable all the debug repos and leave only the ones in my screen shot enabled and then do this to maybe straighten out your system (hopefully):
$ sudo dnf clean all && sudo dnf --best --allowerasing distro-sync