To add further clarification here - I am toon shading my scene; this means I am using the emissive channel for color NOT the base color channel. Unreal is set up to deliver a base color pass in the basic post processing material sets which is great but for people like me who don’t need to use the base color channel it creates either a need for a workaround or a need to integrate that channel and it’s values into my setup. More on my adventures with base color roughness here: https://forums.unrealengine.com/t/removing-light-influence-from-base-color-channel/498834/2?u=srwld
Currently my method is a parameter switch in my shaders that kill all specular influence, I have to render my diffuse out in its own separate pass which is a bit of a time creep but at the very least is a solution.