Well, I can't tell you if it would work specifically in this case, but in general terms the idea should work. I don't know if it can be changed in the middle of a game... probably not. I seriously doubt it would work after the location has already been encountered. But, there are no real differences between some of those special encounters and regular cities. If you find this line
townmap_label_art_idx=
in the city.txt file in the data/data folder, you will see that there are labels for every location with a value other than -1. If you created a label (or just wanted to test this and reuse an existing label) and placed it in the data/art/intrface folder with the other labels, and updated the intrface.lst file, it should work. The location should be saved and associated with that new label, and you would be able to travel there with the click of a button. This should take you to the center of the circle/encounter.