Sounds like you need a new vendor? As an alternative, could you run XP in a minimum VM, which has that particular PCI card's address passed directly to the VM?

Sounds like you need a new vendor? As an alternative, could you run XP in a minimum VM, which has that particular PCI card's address passed directly to the VM? Then make sure that there is no other way into the XP VM (i.e., don't run any other apps on it, and keep it only on the host-only network).