I couldn't launch FBI via the homebrew channel in the guide. So I didin't get it installed by the CIA
Ah, the guide got changed again, good to know. Wonderful how Plailect and Aurora kinda fucked this up.
Anyway, you can try either re-downloading Luma 8.0
here, replace the boot.firm again and hope that it works or try downloading a luma hourly
here, replace the boot.firm and hope that it works.
Replace the boot.3dsx on the root of your SD card with
this one after reupdating to Luma 8.0, seems to be a fix for not working *hax payloads, maybe it'll help. This won't fix the exception handlers though.
If it still doesn't work then, you can try asking on the
homebrew discord for more support.
Your current setup only allows Luma 8.0 to work.
Regardless of it may causing a ban, I really recommend installing HBL and FBI as cias, just so stuff like this doesn't happen/ is easier to fix, then downgrading to Luma 7.1, because of these annoying exception handlers we are forced to see, you will be missing Rosalina though.
It's your choice.