Yes, Eduard, I always shoot RAW (I'm so pixel selfish! lol)
So, is the concensus that I should process one of the images in Capture NX2 because it reads expo-disc data better (or did I just waste my money on an expo-disc??)
Let's step back because I confused the situation. <sorry> There are two ways to set WB with the ExpoDisc. The first is to aim
at the light source and the second is to aim
from the light source to where you will shoot. Most people, myself included, usually use the first method. The issue is that you have so many different light sources and resulting temperatures, right? My guess is that you aimed the Expodisc at the overhead light which is probably close to tungsten in color temperature. As an experiment, you might want to stand in front of the door and aim back at your tripod to set the WB. I honestly don't know if it will make a difference or not.
On top of that, low light shooting increases the potential for chromatic aberration in my experience. (Both my old 50/1.8D and 50/1.4D exhibit this behavior.) It is for that reason, not the Expodisc, that I suggested using Capture NX2. When I have an image with a CA issue, I've tried to fix them multiple times with PS or LR and never been as satisfied as the results from NX2.
Bottom line, you
will get better control of white balance with an Expodisc. As Joseph points out,
any system struggles in the situation you face in this location.
(I guess I'm pixel selfish, too! LOL)