I’m not quite sure what you’re asking. And, this is a user forum so you may be better served by taking your question direct to Sonos support. 
 

But: if you can play your desired station, what’s the problem? Are you saying it won’t play through your Sonos speakers after adding the MyTuner service? If so, is it available through a different service? Might it be a regional/licensing issue? 

I’m interpreting the OP to say it works in the MyTuner app, but not in the Sonos MyTuner plugin for S1. 

Since MyTuner has different servers for the Sonos stream, have you contacted MyTuner? Is it possible the encoding of the stream used by this station is so ‘new’ that it can no longer be streamed by the older and no longer updated S1 Sonos client?

What device are you using the MyTuner app on? What Sonos speakers are you playing on? Is there any possibility of using either AirPlay 2 or Bluetooth to connect the two?