Upper Camera with PointCTRL Controller

I am the developer of PontCTRL, a VR control device for flight simulation. The current PointCTRL HMD mount will cover the upward facing camera of the Rift S. Is the skyward facing camera used only to track controllers above the users head, or is it used for headset positional tracking also?
Thanks
Miles Daddona
PointCTRL
Spec Tech DMT