This is really interesting, It inspired into to try at see if I can solve which area is which, however, if this map posted by StudentOfTheGoddess is right then Catacombs and Hoarfrost Depths should be where I pointed in this image, because comparing the rocheste and cohlen map in on the board it shows that Catacombs should be a little to the right from Ainle and Hoarfrost Depths should be left of Hoarfrost hollow, at that more rocky area.
Anyway this is probably wrong but we can only theorize and speculate for now, but however it is really interesting.