I was able to confirm that the ISO does support UEFI booting (I knew previous versions had, I just wanted to confirm), as you said, the USB key shows up in the boot menu and it does load successfully afterwards.
Looking through the two threads mentioned, looks like I need to dig into how it’s being loaded into memory, here it is today:
:DiskWipePRODDEBUG
initrd ${boot-url}/service/ipxe/diskwipe/DiskWipe_2.31_MC_Debug.iso
chain memdisk iso raw ||
echo failed to boot
prompt
goto MENU
Looking through the ISO in question, I found the /efi/boot/x64 directory where it lays out grub.cfg as:
insmod part_gpt
insmod part_msdos
insmod fat
insmod iso9660
insmod efi_gop
insmod efi_uga
insmod font
loadfont /efi/boot/font.pf2
insmod gfxterm
set gfxmode=800x600
set gfxpayload=keep
terminal_output gfxterm
linux /vmlinuz.x86_64 root=/dev/ram0 rw init=/init video=efifb loglevel=3
initrd /wipe-x86_64.lz /firmware.lz /bcwipe
boot
I’ll be taking a look at this later today once I get time.
Thank you for pointing me in the right direction.