The option to change to the hmd will not be there if you start the game in desktop mode, it will only be there if you start the game in VR mode. The issue is that your computer is seeing the hmd as a second monitor instead of the hmd..
Did you try all of the options I gave you? The fix is definitely within the display settings area as mine did he exact same thing. I just cannot remember exactly what I did to fix it.. Sorry. It was quite a while ago and it only took 5 minutes etc..
I know this is th issue as you can see the static screen within the hmd and hear the game but cannot see it.
Try starting the game in VR mode, then when the static screen is showing, adjust your display settings on computer desktop to turn off the second monitor, or try using the keys "windows Key + Shift + left arrow " if your hmd shows to the right of your main monitor in display settings. For this to work, the game must have focus, press and hole "Alt" then single press "Tab" to elect the game window, then use the key sequence above " Windows + Shift + left or Right Arrow " to move the game window to your desktop monitor...