Hi,
I could see the same behavior in our environment.
Live migration of vGPU VMs works but not the DRS. So if I set one host in the cluster to the maintenance mode all VMs expect vGPU VMs will be automatically migrated to other hosts.
I have to mark all vGPU VMs and move it manually to other hosts in the same cluster on VSAN datastore. The wizard brings a compatibility warning but it will completes without issues.
I hope vmware can handle it in the near future.
Regards,
VM-Master