I have not used a yubikey for boot stuff as you describe, I am a fan in general though.
That said, I have a setup on my servers where there is full disk encryption and a password stored on a random file in a thumb drive or SD card of each machine. If the file / drive is removed I can always type a manual password as well to complete booting. And if I need to do a clean wipe I just delete the keys or intentionally corrupt that sector of the drive, instead of having to do forensic cleaning.






Not at all. Pretty sure I got the instructions from Arch wiki, typical passfile setup just a slightly unusual path