I've been messing around with the shadow matte for days now (shader and AOV) and I have an issue.
In these pictures, I show the masterLayer render, and a comp I did of a shadow matte pass and a shadowless pass. 
This tutorial I followed (timestamped to the shadow matte part) https://youtu.be/XrNQD6AorSE?t=2426
shows this guy just making a shader override, not touching any attributes on the shadow matte he applies, and going into the alpha channel finding a perfect shadow to apply over a shadowless render pass he did prior.
I tried the AOV, I tried the shader itself, I tried a custom AOV with the shader, I tried changing the backlight on the shadow matte to 1, I tried a combination of the AOV and the shader, and I've tried making a render pass collection where it has the override and another collection where it removes the primary visibility of the geo but nothing. tl;dr, I've tried a lot, and my 2 professors are also stumped.
Very convinced this is a glitch. And if the matte isn't a perfect replication, it's still very off in the scene I actually need the shadows for. This render I'm showing to you is just a simplified replication of the scene I need it for.
I have Arnold version 3.0.1.1
