Oh, I forgot that Apple Watches can't pair with iPads. So you can send the document message from the watch to the phone fine, but there's no way to pass that same message on from the phone to the iPad. However, you could use device linking with the iPad connecting to the phone, and set the iPad's layout to open the full-screen document on song selection. Then it would open whenever you select a song, not when you click the document button. But then unless you plan to close the full-screen document after every song, it would be better to just open the full-screen document manually when you start your set, and follow the song selections through device linking so the full-screen display stays open but changes from one document to the next as you change songs. Does that make sense?