Have you checked the book "Yugoslavs of Louisiana?" by Milos Vujnovich. Milos probably published it around 1970. It seems that he mentioned Luke Scobell and specifically where he came from.
If not, some of the Scobelj family live in the mountain-side hamlet of Suttorina, Montenegro. It is in the Konaveli Valley area of what used to be Yugoslavia about 30 miles Northeast of Dubrovnik and not far from Hercegnovi.