How to use two cameras in VR to display 3D object on top of UI panel?

Hello! I'm pretty new to Unity, so I apologize in advance!

I've been unsuccessfully searching for a way to display a rotating 3D object over a UI panel, and as far as I understand from previous questions answered here, the only way to do that is to have another camera that renders the Canvas within which I have my panel and 3D object to display on top of it.

Here's the progress I've made so far: - My main camera's Culling Mask is set to everything except "AboveUI" (the layer where I have the canvas and 3D object). Depth is -1: - My new camera's Culling Mask is set to only "AboveUI". Depth is 0 - On the "AboveUI" Layer, I have the canvas with my panel and 3D object. The render mode of the canvas is World Space: What should happen when the scene is loaded is that by looking at some buttons on the scene, the white UI panel should appear with the 3D object rotating on top of it. When looking away, the window and 3D object disappear. My problem is that they don't appear. The script is correct, I tested it by only using one layer and one camera (but the 3D object doesn't appear on top of the UI panel in this case) Do you know what I'm doing wrong?