Disable fast boot without keyboard (keyboard-less laptop)

I ripped out the hardware of a three year old ASUS (no exact model) laptop and built a case for it out of wood, for hanging on the kitchen wall. Then I started noodling around i BIOS and long story short, I'm now stuck in BIOS because fast boot was enabled by some idiot ... (hint: it's me)

So here's the deal:

• It has no laptop-keyboard, and I can't get the original back
• Three different USB-keyboards have not worked (because fast boot is enabled, right?)
• All boot options are disabled, so I can't access the OS I have on a USB stick
• I have tried taking out the battery on the motherboard, no go

So I boot up, it goes straight to BIOS, and I can't navigate or do anything.

Is it possible to disable fast boot?