Thanks for the reply - yes we have both made sure we have downloaded the latest version (through Steam and Sidequest). We are just using a simple code and we can both see each other in the lobby area. Then the level takes a little while to load but we both enter the first stage at the same time. We have tried both the bank and port levels and the same thing happens every time. We cannot progress and both have to kill all the enemy’s.
I had this problem when I was running v1.14 on Quest. I made sure to uninstall v1.14, then installed v1.15, and now multiplayer works great! I've been able to play via private room with a friend who is also on Quest. I also played with random people via random room, but don't know what headset they were on.
It may be a nice addition if you could see the type of headset and where in the world the person is when you see them in the lobby.