I don't have a subscription to Ancestry so can not view the document. I was hoping that you have seen the handwritten paper.
So there is a connection to former Jugoslavia.
Veliki Grdjevac could now be Veliki Grdevac, Croatia.http://www.jewishgen.org/communities/loctown.asp
Velika Grđevas, Veliki Grćevac, Veliki Grđevac populated place 45°45' N 17°03' E E M U G Croatia 50.6 miles E of Zagreb 45°48' N 16°0' E
Voceljka, Cecilia Grdjovac, Hungary 17 1890 1907
Only she show up with this surname arriving NY EI.
In Croatia Mali Bukovec and Veliki Bukovec.
I would suggest requesting naturalization intent & petition as well as a church record to come to a correct place of birth for your ancestors. Have you located uncle Stevie's arrival manifest?