Regarding Wu's claim that he got R60 to run on Vive, I think it is a half-truth. While Unreal 3 doesn't have full VR support, I've seen videos of people running Unreal 3 engine games on VR headsets, but they don't have any proper depth perception and 3D effect. It's just the original 2D view of the game on both eyepieces with a greatly expanded ultra-widescreen FOV and fish-eye lens effect to make for a faux VR experience. When that super wide FOV is centimeters away from your eyes, I suspect it creates an effect like those old IMAX theatres with giant curved screens where you didn't wear 3D glasses. So more real than 2D but less real than 3D.
I think Wu did something like that, using the Vive headset as a 2D monitor for vanilla R60 with some fiddling around with the FOV and maybe depth of field to make a faux VR effect.