It seems that way yes, S7150 range, which is basically the Firepro series, with varying sizes of core count.
I have the S7150, and it appears from the docs I've seen that they all point to the GIM driver which I guess is what would need to be understood by unraid in order for it to partition the GPU up for virtualization.
I can see the repo has been forked many times, I've looked through a few and it looks like people have customised it for use in various forms. Perhaps that's the right path here, but it certainly is niche.
When I'm back from my holidays I'll look into this all further, I'm a developer and wouldn't mind a new project for the new year!