Genealogy of the family of duke Petar Vukotić of Montenegro is well documented and researched. I suggest you contact one of the local family researchers to see if there is any documented direct link between your ancestors and this family. Surnames were often the same within a clan, and the link may not go further than common earlier origin.
According to publicly available info, one researcher, Nikola M. Vukotić, has a book that is soon to be published about the duke and his life.
Links to two newspaper articles about the duke Petar Vukotić, father of queen Milena, where the author researhers are mentioned:http://www.dan.co.me/?nivo=3&rubrika=Feljton&clanak=...http://www.pobjeda.me/arhiva/?datum=2005-03-02&id=55913
"Rodoslovlje" Serbian Genealogy Societyhttp://www.rodoslovlje.com/en