Thanks for the info! 
Well, I am having zero luck so far. I am familiar with BIOS Flashback, but for whatever reason, it never begins to flash the BIOS. It blinks only once or twice and stops. I checked both BIOS chips to make sure and neither changes from the version currently installed. Is a PCIEx16 to NVME M.2 Adapter and boot drive a lost cause?
Asus USB BFB can be very picky sometimes and also depends on motherboard models… smallest USB, different brands and FAT/FAT32, M5E.CAP is the name.
Gotcha, smallest I have is a 4gb anymore haha. I tried my old san disk, a Lexar and a Samsung so far. I’ll see what else I can dig up