I’ve been researching uses of VR for exposure therapy for PTSD and am wondering how I would set up a “game” to allow player 1 to view the world through a VR HMD while player 2 (the therapist) uses a separate monitor to control the world.
Would like player 2 to have their own interface on a separate monitor and be allowed to cause events to happen on command. Player 1 is simply observing the world through the VR headset.
Do you mean both players use the same machine? Your description could be equivalent to two players on two different devices, this setup would be fairly typical. It would grant your application more flexibility and would be recommended. However local multi player is perfectly fine too.
Multi interface from the same machine is fine with the engine: think consoles with multiplayers. Or better: take a look at the testing multiplayers documentation.