Yes, you can remove the rocker cover and observe the valves. If only the first few move, the chain is connected and the cam may be snapped. If none of them move, I'd expect the chain drive.
The tubular cam can break at any point, and not necessarily make any noise. The cam will simply be retained in its journals and not move.
https://www.youtube.com/watch?v=3kH0Ttgl1lo