You may want to ping Amazon directly, they are responsible for what is shown to you in the Sonos controller. Sonos doesn’t do any filtering of the data presented to them by the Amazon server. 

I have sent them a message, but won’t Sonos have more weight than a single customer?

I wouldn’t think so, companies tend to pay more attention to sources of revenue. You pay them, Sonos doesn’t. 

Although you could argue that Sonos represents a large number of users. You’ve already posted here, so why not ping Amazon?