Couple of things:
1. Have you check the HIIClient.log stored in C:\ldprovisioning? Does it even attempt to install the driver package?
2. Instead of assigning it to a VGA adapter try expanding through all your Device Manager entries and find something common across all your models (like processor) with only 1 entry inside it. If you point your package to this you can be sure that 100% of your machines have this device installed.
Thanks,
Peter