Dear,
I am Marta Balan, I was born in Sombor, Bacska, Voyvodina, ex Yugoslavia (today Serbia) and migrated to Australia as an adult (
http://www.wikitree.com/wiki/Balan-15 ). My native tongue is Hungarian and second native tongue Serbo-Croatian, my mother was a teacher of Latin language (the language of the old registry books) which I studied too and I can read German as well.
I am able to give a contribution to your search: Jercucz is NOT a name or a word in Hungarian! John would be in Hungarian János.
I am 100% sure that the name above reads in Hungarian as Ferencz Klaszki, a Hungarian name for Frank, written with "cz" at the end, which is how the letter "c" was written in the books in Latin.
A man would not take the family name of the wife, but immigration was an exceptional situation. There may have been some benefits to do that.
The original documents do exist in the registry offices. However, the place of birth in the passengers' list is not Bacska Palanka, Bacska, but Bocsár (Botschar in German) in Banat. At the end of the 19th century Germans moved there from some nearby places and there were more Germans then Serbs (not today). There were always Hungarians there too. The place seemed to be predominantly Catholic at the time, it has an old Catholic church. See:
http://vajdasag.rs/Bocs%C3%A1r The place is in Banat, one of counties of Voyvodina Province (Vajdaság those times). The province was abolished in teh recent war for political reasons, but it always stands for a distinctly different history of the: Austro- Hungarian Monarchy.
Ferencz declared himself as Hungarian (Magyar), which may mean that he was a Catholic, no 100% sure..
The registry offices have entries from 1900 onwards. Before 1900 the books used to belong to churches, but were transferred into the local archives. I was told by a Catholic Bishop that a new law came out recently which requires these old books to be returned to churches. That transfer may be in process now, though not complete. It would be important to know what was their religion.
I also checked the Ellis Island book enlarged and could clearly see the names: Ferencz Klaszki and Margit Schneider, her last name written there also as above the name of Ferencz Schneider. Where did you get that name? In the passengers' list he appears only once, I suppose. In the passengers list they had different family names and Anna's name was Schneider, not Klaszki, may well be that they were not married at the time.
If you need more help, please do not hesitate to contact me on balan609@gmail.com
Good luck!
Cheers,
Marta