Fugitive's right, but just to clarify, what I think he means is you can only have one analog control assigned to something like that, which is correct.
Extrapolating a bit, are you trying to be able to use views to look behind you etc with your VR setup? If so, you need to assign button presses to say, look behind you. I am unfamiliar with Thrustmaster gear, do you have an option to make that stick function as an 8-way or 4-way hat? If so that might get you where you want to be. If not, if it has another hat that is switches, that should work.
Additionally, when you're pressing the view switch, like say to look back, if you hold the button then move your head in a direction and hit F10, it will move the location your head centers on when you hold that view button, the same as when you're not holding a view button. So you can set it up to be always looking to the side of your seat when you look back, etc.
Wiley.