I did this on my laptop with the touch pad, so please forgive the bad selections. I was also using the JPG downloaded from here, so I didn't have the benefit of the raw file.

I was going to take it to my main machine, but I'm pretty sick today and I have three big events Fri, Sat, & Sun, so I'm staying in bed. If you look at where the selections are a bit sloppy, you can see just how much blue there is in the original.



Here are the steps I took:

Select mtn, Copy to new layer > Filter> Blur>Average.
Add Levels adjustment layer, click with gray dropper on solid color
Delete solid color layer, adjust levels layer to about 50% opacity
Merge Down, Reselect mtn

> selective color > add black to blacks, black to blues and black to neutrals.
Hue / Saturation, add saturation to master and darkened

Select Sky, > selective color > add black to black, black to white.
Hue / Saturation, add saturation and darkness to blues