How do a i create a mask or an occlusion material? I want to show a hole going into a wall or floor.

I'm trying to figure out what I need to do to create an AR asset that looks like a hole going into a wall or floor.

I figured this would be easy using some occlusion material but I haven't come across anything yet.

I tried a "holdout" shader in blender and it didn't work. I also tried flipping normals to see if I could get a cylinder to render the inside only, but no luck.

Any advice is greatly appreciated!