To be clear, the article cited says the original model built for the show, "was actually a striking purple-blue and light green."
And then, "[Round 2's] approach was to paint the ship a more overall grey while maintaining a hint of original purple and green. That way, everyone should be able to relate to it. I also weathered it to make the model more appealing, even though the originals were not weathered."
I'm merely putting data points out there, and ones that in this case happen to reflect the article quoted above. I did say the color could be lighting, but just raised why I thought that might not be the case. The fact is there are sources that say the model was not gray, and I'm just trying to figure out if they are or are not correct.