I have tested this out on an HP 8200 Elite SFF that has AMT Firmware Version 7.1.3.1053. I have also tested this out on an HP 8300 Elite SFF that has AMT Firmware Version 8.0.4.1.441. I was using the Intel vPro Platform Solution Manager and VNC Viewer Plus to KVM into the machines.
That is along the lines to what I was initially thinking, it might be related or a separate issue but on a normal boot if the computer was powered off improperly and boots to "Start windows normally or Launch start up repair" you are also unable to select either choice as well with VNC Viewer Plus.