Updated the BIOS
Re-applied BIOS settings
Server Virtualization
Enumerate IOMMU
Booted unraid
Booted VM
Profit.
@bastl - thanks for the suggestion there
Side note - I removed the acs override before attempting bios update and same result
Side note 2 - since i removed the acs override already, i did not re-enable that function before attempting the BIOS upgrade as well. (i have updated bios and no acs overrides set currently)