How to get spherical extinction for volumetric fog

Problem:
Spherical extinction of volumetric fog is not working, even though I have copied my blueprint exactly from the feature highlight.

Feature Highlight:

My material I have setup:

What is rendered:

Desired:
A spherical fog that wraps over another sphere like an atmosphere.

I am not using the built in atmospheric system because it only supports one atmosphere at a time. I need multiple atmospheres to be on the screen at the same time.

Any feedback would be greatly appreciated!