No, it wouldn't work with the Marmitek Split, since you'd need a HDMI-cable to connect to the AV-Receiver to send the audio. Since SONOS is connected via Wifi this is not going to work.
Alternatively, you can use this split to send the signal over a 3.5mm audio cinch and to connect it with whatever speakers, AV-Receivers or Hifi compact systems you want.
Delock HDMI Audio 5.1 Extractor