So, as noted in the other thread, I've been able to get this working with 1 monitor. The exact steps were as follows:
1. Install the nVidia K1 cards in the R720 hosts
2. From the vSphere client, enable the card for passthrough
3. Reboot the ESXi host
4. Shut down VM
5. Add Grid K1 using Add PCI device from edit settings in VM
6. Power on VM
7. Log in using vsphere console
8. Download and install nvidia drivers. Current is here. As of this writing
9. Reboot
10. Connect to VM using PCoIP with ONE monitor only connected
11. Note it is still using VMware 3D Drivers by checking dxdiag (also the Nvidia control panel will not launch)
12. Disable VMware SVGA 3D adapter
13. Screen blinks, and now able to Launch Nvidia control panel as well as check DXdiag to confirm using Grid card.
*note* I did not have to run the montereyenable command, however I did so after, and the screen went black. When I reconnected, I was still using K1 card for video.
*also note* This does not survive a reboot. Steps 11-13 have to be re-performed each time. In fact, I found that after a reboot, I had to re-enable the VMware SVGA 3D adapter (it was using some generic VGA driver), then reboot AGAIN, then connect again and disable it before the K1 would work.
So, hoping this becomes properly supported in the near future, as it's pretty much useless as is.