Shaddow Matt passes invisible for sun off

Hello

I was searching theard like mine but I can’t found.

Here is my problem. I want render passes for shadows. When sun is on have shadow matt pass but it have normal shadow on it too, why?
Bigger problem is when sun is turn off , like cloudy day, and we have shadow only from sky. Than any shadow on pass noraml varyshadow and shadow matt is invisible not creating on passes, why?

I prepare pictures to show that, I hope this will be much clean.

I use vray buffer and irr + ligh cashe.

regards