Shadow Catcher Problem

[jovcem]

Im having some problems when rendering shadow on a matte material that is produced from a directional light.

The pillow is a matte that receive shadow from another pillow (as seen on the 2nd image) but on the lower part of the pillow there is no shadow at all, and also on the lower part the shadow gets stronger.
This render is composite of two renders.

Here is the render without separating the elements


The compositing works fine when not using a directional light.

I have found this thread that might be the same thing.

[jovcem]

I think I've solved my issue, I had GI Amount to 0 on the matte object property.

EDIT:
Though I have another question, What are the best setting for the smaller pillow that casts the shadow, right now I have a material wrapper on that, with Alpha contribution set to -1 because I want to not appear in alpha, is this enough?

[jovcem]

Im still not getting some of the shadows on the lower parts.
It seems like the GI is affecting those areas, but why?

1.Complete render

2. Shadow Composited from shadow catcher material