Sean,
Unfortunately, we can't put 802.1x parameters into firmware using USB Key - for further details, read pag 135 of Intel SCS Manual - that is the reason that you are not seeing in switch and RADIUS this machine as supplicant. In order to achieve what you need, you may use an USB Key with WinPE and into Windows Pre-installation environment, provision the machine using Host Based Configuration method. However, if your RADIUS requires AD integration, you probably won't succeed since it's required to connect to you AD to create AMT object and 802.1x will not allow - unless you provide access through a quarantine network.
Have a great weekend.
-Bruno Domingues