Varying Emissivity isn't changing thermal results?

Hi all, 

I am new to the SolidWorks forums so I will try to upload all relevant files, but please point me in the right direction if I have any missing. I've done a search to see if I could find relevant discussions already posted but have come up mostly empty-handed.

I am modeling a system that utilizes a graphite heater to heat up a graphite disc. I used a "filler" Nitrogen part since the assembly is enclosed in a vessel that is evacuated, then filled with pure Nitrogen. The walls of the vessel are kept at a constant 25C, so for simplicity, I didn't model the containment vessel and instead set a temperature condition of 25C on the outer faces of the N2 filler part. 

What I want to achieve is a comparison between the thermals of the graphite carrier on a brand new vessel (emissivity = 0.05) and after surface degradation (emissivity = 0.3). The problem is currently that I have found the same exact results when I'm sure that they should be different. I am assuming I have settings in the radiation simulation setup incorrectly but I am not sure.

SolidworksSimulation