If anyone else is struggling with this, I have found a temporary work-around that seems to work but is by no means clean. When I tick “skip assigning gamepad to player 1” (the VR player) then the first of the two other characters gets both the touch controls and the first xbox controller sent to them. I simply made custom events in my VR player and every time a Touch button is pressed then the pawn triggers the custom event in the VR pawn. Unfortunately this doesn’t seem to work for trigger axis values but the simple ‘on’ or ‘off’ of each button works fine.
It would be really great to have more control over how keyboard+mouse/gamepads/joysticks and any other input devices are assigned to pawns by the player controller in blueprints.
I hope this is a help to anyone else struggling with this issue.