The current image that is downloadable is not creating a valid bootable drive when using the ISO to create a MBR or UEFI USB drive. Both methods produced the error "Unknown filesystem" then failed tot he GRUB Rescue prompt. I tried redownloading the image 3 more times with the same result, so it is not a bad copy of the ISO.
I have successfuly booted the target system with a Debian Live 10.6 USB UEFI drive and it works every boot. I have tested 5 other OS versions that are UEFI and every one booted except TrueNAS SCALE. The hardware is working correctly. The BIOS is setup correctly.
I have tested this image on multiple computers and athey all end at the GRUB Rescue prompt so I know the image is the issue.