I have exactly the same experience with my ARC A750 eGPU and an 11th Gen Framework… I jumped through the hoops to get that tool running (did nobody mention that you’ve got to get a UEFI Shell up somehow, too - and learn to use it (hint: it’s like DOS - FS0: is the USB stick, cd to the path, run it like a program, etc)? haha). Admittedly I didn’t get a “Before”, but in the After, it’s got a half-opinion - says it’s disabled in BIOS, but enabled in the specs.
Maybe it’s just confused by Thunderbolt?
BTW, the ARC A750 worked wonderfully (Satisfactory in DX12 at least locked at 60fps - the ARC is full of quirks and in DX11 it was struggling at 20fps, and Vulkan was a corrupt garbage fire) even before ReBAR tweak was applied.