Just as an experiment, Colin and I overlaid the Dragon Pass board game map over our Dragon Pass region map. Wonderful success! Most board game locations were within a hex of the final map locations, and many far closer than that. Entirely possible to play Dragon Pass using this map.
The hexes of the two maps do not line up – that’s a byproduct of the sheer nightmarish size of the map. But hexes from both maps are the same size (5 miles per hex). Given that the Dragon Pass board game map deliberately moved some locations to fit the board better (so for example, no city is on a river hex, etc), that’s getting things pretty darn close.