Hello!
Me using "grub", I might be wrong with the following observations/advice, but nevertheless:
I assume, that you actually boot kernel and initrd by UEFI-entries, having nothing to do with systemd-boot in the initial phase. Your problem are the unknown kernel- and initrd-names, right?
Now, when you're using an installed system, there is always a (symbolic) link in the root-filesystem (/) pointing to the actual names: "/vmlinuz" and "/initrd.img". When you use them instead of the "real names" in the UEFI boot reference entries, a kernel-change should go by unnoticed. If your "boot to terminal" did work until now, it should just continue to do so.
If you are booting a "live" system (.iso), well I had the same "problem" or actually more nuisance myself. But when you're looking at the posting ([DE]
Neutrale Kernel- und Initrd-Bezeichnung in /boot) just before yours, there "towo" showed a way to achieve the same thing - using "neutral" /vmlinuz- and /initrd-names with ISO-images. It will work with the
https://testbuilds.siduction.org/kde/siduction-Masters_of_War-kde-amd64-latest.iso he kindly provided, and I do hope that this "feature" will be included in future Siduction-ISOs, too.
As to the specific "boot into terminal", I need to see, how this is (or was) done beforehand. Hopefully someone with more experience or knowledge will step up here and write something about it. But it might work, already, by just applying the changes suggested above.
All the best!
