@mr412I only had a brief look at Surveillance Station, but it's not something I was interested in. So I don't know how to get it working.
Getting an Nvidia card showing in Synology is pretty easy, just follow the above steps.
I am more interested in using it in Docker for something like CompreFace etc
The problem is that although we now have an up to date version of Docker ( 20.10.03 ), it's pretty much useless without getting nvidia-docker2 on there somehow.
https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/install-guide.html#docker
It's not something I have had time to investigate though.