Doing the hazing is a good point, but I suspect that's later in the process. I'm no expert here, but from what I've seen is the artitst puts down some base coats, then details in various passes using fairly strong colors for many detais, while adding whte to the mixing of other colors as the process proceeds. Eventually most things are covered with the "haze" , then the whole vista is overcoated, sometimes multiple times. This depends a lot on the distance being portrayed, so more distance, more haze.
Graff will get around to it, I'm sure. It's a great scene developing!