Hi cjnot,
I know it way too late to replay to your question but I thought may other benefit from my answer.
I convert my PC at home to a server and installed ESXI 7.0 U2.
I have single AMD GPU in the server. The AMD GPU was exhibiting the symptom noted in the link you provided but when I move the host display to motherboard HDMI the AMD GPU stayed active after rebooting.
Now I'm trying to get display from Mac OS guest through the GPU.
which me luck
