Affect Distance Field Lighting and NOT cast DF shadow?

Thanks, but no - neither of those appear to impact DF shadow casting. It’s much more visible in low-light settings on the shadow-side of objects. My example here isn’t great, but you can see it near the end of the video.

Inisible cube has masked mat with 0 opacity mask and ‘Affect DF’ on. The visible cube has ‘Affect DF’ off.