Cast shadow from light in another channel?

Here’s the scenario, I have a dynamic moving character in an environment that is all light by a stationary distant light (it’s supposed to be sunlight). I am getting bad, low resolution blocky self shadows on the highly detailed character so I put the character into channel 1 (from channel 0 like everything defaults to) and then added a spotlight set to only affect channel 1. This spotlight simulates the color and angle of my original directional light. I can now fine tune the shadow bias on the spot light and get the look I want (the character pretty much stays put so I don’t have to worry about him leaving the spot light cone angle)
So what I want to do is keep the existing distant light on channel 0 which lights up the scene and all its elements…but be able to have my character which lives on channel 1 still cast a shadow from the distant light onto the scene etc (just not actually be illuminated by this distant light) I know this setup is possible, I’m just having a tough time tracking down what I need to do. Thanks!