Purple cast in shadows. How something closer to maroon? I've had this effect with Foma MG. This would be nice in the print you showed, because of the nice horizon line, which allows partial toning and bleaching. Probably won't get the same effect with another paper. But maybe something more pleasing, too.
At least for foma: very short bleach (shadows are bleaching too, whether you can see it or not), followed by sepia. You won't be able to see the sepia in the shadows either, but other toners (gold) can see it.
Re-bleach the lower shadow portion of your print to the first hint of bleaching effect. Of course, this will take a little more time than the first bleach. This time, no sepia. Just fix and wash. Followed by selenium to taste, then gold.
Obviously, with fiber paper and all the wash cycles, this can be a long process. And with all the "snatch points" involved . . .aye-yi-yi.
Anyways, this works for me with Foma MG. I don't keep notes, so can't say much about what sepia formula (1:5 yellow or 5:1 brown) makes the purply hue.
If you go to my gallery and see the hue/shade/value you are thinking of, I would be able to describe this process more cohererently.