I spent a half hour or more on the phone with the SiriusXM's streaming team. I got their number from the online chat rep. Of course, that was just the regular customer service number. But the regular rep did eventually get me to their streaming team. They eventually decided they have no ability to enhance the Alexa SiriusXM skill to get it to tell me what music is playing.
All it ever did before was tell me the channel name.
But they did give me a phone number for the Amazon digital media team. That number was 877-375-9365. After another half hour, the rep finally figured out what my issue was, and told me I could fix it via the Alexa app. So, they hung on the phone with me until I downloaded and installed the Alexa app again, logged into my Amazon account, and approved that login via the web.
What a gnarly mess.
Anyhow, within the Alexa app, there is Settings --> Music and Podcats --> Default Services. If you change Default Services from Amazon Music to SiriusXM, now the Alexa skill will tell you what it's playing. But you have to say "Alexa, play <SiriusXM channel name>". You cannot say "Alexa, play the SiriusXM Spa channel" or she has no idea what she is playing.
Unfortunately, now she not only responds correctly
when asked, but also she announces both artist and track before playing each and every one! Argh. I can't win.