Question URP stacked camera follows head. Don't want it to.

I am making a Hololens app with unity. There is a scene with a base camera that displays UI. I've added a second overlay camera that only shows 3d models on a particular layer. This camera is manipulated to make the models appear to rotate, translate, and scale. It works, but the nominal position of the models follows the user's head. And I would like it to either remain static, or follow the UI. How can I do this?

 

If I project the camera onto a plane, that seems to get me what I want. But is there a way that I can make result clear except for the 3d model?