Beige
With some grey areas.
Just made a new capture of the scenery, from the 4k youtube version, and tryed to enhanced the pic to get more details by tunning the levels, the luminosity and the contrast.
If it can help.
I am pretty sure frontier learned from the past. we already saw that in the trailer for the alien structures. Point is: You cannot get the picture exactly like in the trailer.
There is just not more dust you can add. Get towards the core and that takes over. Get out and the whole galaxy lights up. From the outer arm i could not see any dust. Only a bright band of light.
These are the two images that were enhanced (mostly made brighter) ... just for reference.