Correct, I don't get that error when adding as a "PCI Passthrough Device" manually.
But I think you might have some other issue. You should be seeing the device name in the list, something like "0000:00:02.0 'Display controller': CoffeeLake-S GT2 [UHD Graphics P630] by 'Intel Corporation'". But for you it sees TrueNAS is having trouble obtaining the device info more generally. Very weird.
What version of TrueNAS are you running? I'm still on SCALE 23.10.1.3. (Haven't updated to 23.10.2 yet.)