1832, though "John Marshall has made his decision; now let him enforce it" is apocryphal.
Also that was Andrew Jackson being a racist so maybe not the best role model.
I'm not aware of SCOTUS directing federal marshals to enforce their decisions. That may not ever have been tried.
You want KVM.
But I'd check the performance on the NAS first. They're not really built for VMs so you might be missing hardware features, but I'd check resource usage to see if you're maxing anything out. And try reducing resolution, color depth, etc. to make it easier.