Ok guys let's figure this out: how do I find where the windows install iso stores it's bootloader code, because that's what I need to find. Afaict they basically nuked the hell out of iso9660 for windows 10 bootable CDs, but the bootloader is there somewhere.
ISO9660 boot works using out-of-band images (El Torito specification). Those images can be raw boot files, floppy disk images, or hard disk images (BIOS emulates for images). See https://wiki.osdev.org/El-Torito . For EFI it's a FAT floppy image with EFI/BOOT/BOOTX64.EFI in there.
