While the iFi Stream app is generally not good for much else than maintenance issues the Web Radio function is actually pretty good and includes a number of FLAC stations. Since mConnect doesn't have a radio function it keeps you from having to use Airplay for Internet Radio. Since the iFi app is just stripped down Volumio the new Volumio 3.0 paid version should work with the Zen Stream and it is a full function app.
If you don't get it to work the only other suggestion if it doesn't cause "domestic" issues it to shut everything down all the way back to and including the router and the re-boot each piece in order going forward from the router after the previous piece is fully online. That should re-set the network and allow the Zen Stream and iPad to see each other again.