MSI MEG X570 Unify vs Gigabyte X570 Aorus Master for VFIO

Regarding the bottom pcie slot, I was reading the MSI Unify documentation the other day, and the page on the PCIe slots seemed to suggest that the bottom slot wasn’t compatable with graphics cards, so I would guess that this isn’t possible. I would be interested to know if it’s possible to run the host/bios card in the second slot though, as opposed to your current setup