I already answered by mistake with an old account, so you may get this twice… sorry about that.
The author of the tutorial uses a VR Pawn derived from the Pawn class. By default a Pawn doesn’t have any collision capsule nor a mesh which can collide with another actor. This is the reason why you don’t get any collision.
Mainly you have two ways to add collisions to your VR Pawn. 1) Manually add to it a collision capsule as root component or 2) edit its parent class and set it to Character. Characters have by default a collision capsule as root (plus a movement component which you won’t need here).
With that done, your Pawn should be able to collide with other actors in the scene which also have collisions enabled (something like Block All Dynamic for both should do the job). Give it a try and let us know here if you still have issues.
Cheers,
Marco.