No. The Sonos ‘app’ is not a player, it is merely a remote control that tells the Sonos devices what to do. And while some Sonos devices can receive a Bluetooth signal, ignoring the Sonos controller, none of them can ‘send’ a Bluetooth signal that your Zepplin Air could connect to. You may be able to connect via Bluetooth to both a Sonos and your Zepplin at the same time, but you’ll be using a player on your PC and the Bluetooth, and not the Sonos controller. 

I was afraid of that

Thank you for you response.  Much appreciated. 

If (and it’s been years since I looked at one), the Zeppelin has an analog line in, you could connect it to a Sonos Port, and use that to power the sound on the Zeppelin. But things get complicated as you’re using S1, and you may need a used CONNECT instead….either way, there is an expenditure.