Thanks for your response,
Both keyboards work during boot, in the live usb environment, and while booted into my windows partition, the input only stops once I am put into the LUKS unlock screen, so it’s can’t be a hardware issue. They were also both working totally fine when I initially was using the keyboard, before I upgraded my system and powered off.
I mentioned my alterations to the mkinitcpio hooks because those were the suggestions that solved the same (or a similar) issue for other people from some threads I found (It’s not letting me post any links because my account is new, but one of the posts is titled “Keyboard does not work at LUKS password prompt” in archlinux forums), something about autoload not finding the correct drivers before I get thrown into the LUKS unlock screen. I also did try your suggestion of leaving it unplugged during boot already, to no avail.
I use the 419 kernel because the non LTS kernel I was using before was giving me grief - I don’t remember exactly what though, it was a while ago