Yes, the info is actually correct.In 1913, Transylvania was still part of the Austro-Hungarian Empire, and would remain so until 1920, when it became part of Romania proper.This is despite the fact that the majority who lived in Transylvania were ROMANIANS by ethnicity and language.There was a minority of Germans there (who called the area Seibenburgen, or Seven Forts, after the seven major towns), and Hungarians, who called the area Erdely.
Sibiu is still a county in Romania, and the county seat is Sibiu city.The Germans called it Hermannstadt, and the Hungarians called in Nagy-Szegben (spelling is wrong on that; sorry!).
Talmacu (tell-MAH-choo) is a village outside of Sibiu.It has traditionally been a Romanian (read: ethnically) village since it was founded.
You should go there, for you will likely find relatives you never knew you had.They will welcome you with open arms and tables full of food and casks full of alcohol.
I lived in Sibiu for 2 years and loved it; I adopted a son from there, and I'll go back to live again some day.
Take care and good hunting!
P.S. Petra and Maria Stefan (SHTEFF-ahn); the 's' has a little tail under it that tells you you pronounce it "SH".