XPS 8930 on BIOS v1.18

I downloaded a few versions of the BIOS to a FAT32 USB. Booted PC and hit F12. When I choose the flash bios option, it brings me to the BIOS update screen, where I select the BIOS and when I tab over to the Upgrade button and hit the Enter key, I get a popup: "Unknown command".

Mouse doesn't appear available in BIOS (tried with a wired mouse connected to USB 2.0 port on the back of PC), so keyboard seems only option to navigate the menu.

Any ideas on what the problem is?

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