Not sure if this is correct way (as the way shown in the tutorial doesn’t work for me either) but I forced the tVR to work on my pc by starting the SteamVR in safemode and after few moments a pop up showed up with asking me to restart SteamVR, before clicking it I set up the tVR to ON and than press on the pop up.
After a the restart SteamVR turns and right after that the driver4vr also turn on,from now everything should work just fine.