Why changing example to port it to VR doesn't work?

I just checked the dragon test on my vtk master build and it worked fine. I started steamvr first then I ran it as

C:\Users\ken.martin\Documents\vtk\bin>bin\vtkRenderingOpenVRCxxTests.exe “TestDragon” “-D” “C:/Users/ken.martin/Documents/vtk/bin/ExternalData/Testing” “-T” “C:/Users/ken.martin/Documents/vtk/bin/Testing/Temporary” -I

Not sure what is off on your example but if you can get the dragon test working maybe that will give you a reference. You might need to copy the controller files into your bin directory. e.g.

01/29/2021  11:33 AM             1,652 vtk_openvr_actions.json
01/25/2021  12:46 PM             2,303 vtk_openvr_binding_hpmotioncontroller.json
01/29/2021  11:33 AM             1,760 vtk_openvr_binding_oculus_touch.json
01/25/2021  01:14 PM             1,908 vtk_openvr_binding_vive_controller.json