if you are still interested for research of roots of your great grandfather Franc Potisek, I have a complete tree of his ancestors from 1750-1900. It is too large for this forum, I can send you to address DSawyer1@indy.rr.com
, if it is still active.
Bruna Draga is not a village but a back part of village Velika Kostrevnica (velik = great) near to the next village Lupinica, slightly lifted in a side valley, having only one farm and two homes in 19th century. The ancient home name of this farm is "At Pilpoh's" and is now Velika Kostrevnica 25 (55 in the 19th century), the name Bruna Draga has not been known anymore today. The surname of today's inhabitants is Sirk. The Franc's brother Janez inherited the farm, married Marija Smuk (1912), but he died soon after the marriage. His wife married secondly Anton Sirk (1918). I do not know personly the Pilpohs.
Besides Franc, yet his brother Anton (b. 1889, to US 1913), sister (Franciska (b. 1887, to US 1912) and niece Anton (b. 1894, to US 1923, d. 1974 in Cheswik, PA) went to US in diferent periods, but it seem some returned to Slovenia.
Interestingly the maiden surname of your great great grandmother Marija (the wife of Ignac) is also Potisek, a line from another farm "At Bregar's" (Velika Kostrevnica 60). This line is common to the line of Simona Lesjak with common 5x great grandfather and hypothetically, but not proved to my 5x great grandparents.
Velika Kostrevnica is a village of the commune and parish Šmartno (St. Martin), a town near Litija and 30 km easterly of the capital Ljubljana.
There were 185 single surnames in the form Potisek (mainly central Slovenia) and 212 ones in the form Potisk (mainly in northern part) in 2009 in Slovenia.