I have just completed an installation on a NUC. Initially I ran into the exact same issue but managed to get it to work.
This is what I did
- Use Rufus to create a USB bootable drive from the ISO file.
- Press F10 during the the NUC boot up to access the bios boot menu
- Select the USB drive as boot drive (! The drived appeared in the menu as a USB drive and also as two UEFI drives, only the USB entry worked)
Good luck.