You should put a similar request in to the Synology folks, and suggest that they look at the Sonos partners page. They can see how to join the Sonos ecosystem there.

Or, by Synology Audio Station, do you man a physical device? There are many, many threads about how to connect to a Synology device using SMB v1 already. And the community has also been asking for something other than SMB v1 for years, and there are multiple threads about that request, as well, many of which contain speculation as to why it is difficult to do, and even why Sonos may not want to dedicate the resources to do so. 

That’s a good idea and I shall submit it to Synology. However, it is Sonos that has caused incompatibility in the first place by holding onto an ancient and dangerously insecure protocol (SMB1). The onus is on Sonos to support SMB2 and move into the 21st century or to show some integrity and stop pretending that they support local media servers. Asking users to support the networking equivalent of Adobe Flash is just irresponsible. 

This has been covered at length in many other threads, perhaps you should add your comments there.

Synology just need to port the SonosLibraryService.exe to their OS. Its just a simple http-based server, the details are easily available by a swift decompilation of the exe (its a simple C# app). The only tricky bit is initial Setup, and the account secrets management.

Can Synology run .NET Standard apps? I know some Linux distros can.

If I was laying blame between Sonos and Synology, I’d point the finger at Sonos.

However, the best fix seems to get Synology Media Server recognized as a service in Sonos-land, and the onus would be on Synology to make that happen - if I understand things correctly.