Sync Non Player Object using Ray Wenderlich Multiplayer GPGS Tutorial

Creating a Cross-Platform Multiplayer Game in Unity Tutorial by Ray Wenderlich is awesome.
Having problem in syncing non player object like ball in game like soccer.
How can we sync non player object with all player interaction with it and sync its data across all efficiently?

I have already implemented game owner mechanics. So that I can spawn ball in all players by game owner, but if other players interact with ball, how can we sync accurate data across all?

Any one has done this before ? Any idea?