***UPDATE 2***
See posts below for fix. Essentially the most obvious symptom of my particular issue was the VM not booting and the system log getting completely filled with a message like:
vfio-pci 0000:65:00.0: BAR 1: can't reserve [mem 0x38bfe0000000-0x38bfefffffff 64bit pref]
***UPDATE***
I dumped the BIOS myself and that still didn't work. But I did discover a work-around to my problem. If I boot up the system with no display attached, my board will leave