In answer to your question - Docker, not really the correct way to go with this.
LXC - using LXD VM's - yes, it is possible and it works.
I have an Ubuntu host, lxd installed, created a Win10 VM and was able to pass through my Physical AMD RX 6600. This is my first stage of testing - next will be to attempt to chop up the 6600 and hopefully have 2 LXD VM's with a 4GiB GPu Profile attached -
For the moment, the entire Physical GPU to the lxd VM, yes without question.