If Saurfang was headed in this direction, it would have been difficult for him to avoid the Three Corners watchpost.
We could simply walk in there and demand information, but I have a feeling that they would not part with it willingly.
So we will take another approach.
I have procured this potion from our alchemists. It will turn us into--ugh--humans for a while.
We can then question the guards. Perhaps someone saw something.