@PPA
You can see mosT useful features is under IntelRCSetup tab ,included you need IIO Configuration. This is an external module and i thought it's hard or a big work to let "IntelRCSetup" appear in the bios menu.
(If on Msi x99 board ,we can use swapping method then link to IntelRCSetup tab ,but on ASUS it's a big work.)
So ,i'll suggest you to change settings value via AMIBCP then re-flash the modified bios.
If this board has flash back feature you can use it to flash bios. If not ,you could use Intel fpt tool(version9) to write it. Or you could use i prepared
tool package.(It's also intel fpt9 ,but i put batch files to simple the process)
Your processor is included 28 lanes ,it should is x16 ,x8 ,4 to pci-e slot ,the first pci-e slot should is x16 ,insert the Hyper m.2 card to it then try below settings and check it's available.
Under IIO 0
CPU Lane Type = cpu 28 lane
IOU1 (IIO PCIe Port 3) = x4x4x4x4
If it's invalid ,you could try other combination or try it under other IIOx