Something wrong with my hole I am doing the Introduction to Camera Tracking in Blender tutorial by Blender Guru. 



Somehow, I managed to mess something up, and supposedly hidden parts of the hole are showing. I don't understand where I went wrong. Thoughts?

Here is the .blend file:
You can also mix the material of the sides of the hole with a holdout shader while using the backfacing output of a geometry node as the fac input of the mix shader.

Without the holdout shader:



With the holdout shader: