I find your information fascinating about the Drobnjak clan. My grand mother always claimed to be a Drobnjak, in fact her maiden name was Drobnjakovic. My great grandfather (her dad) came from Montenegro, his name Milenko Drobnjakovic, to Belgrade as a 13 year old boy. He was the youngest son sent away from home with a piece of bread and a few golden dukats (3 i believe) and asked not to come back again as the family was poor and could not support him. He arrived in Belgrade as a young boy and there learned the bakers trade by working in a bakery for many years, sleeping in the bakery and saving every penny he made. He eventually had enough savings to become his own master, he built a house and bakery in Belgrade (still stands there and the baking owens are protected historical items, bakery is a convenience shop nowadays), got married and had two daughters. The name died out with them.
I hope you get this message as I think it may link into what you wrote about.