Slovak communities in New Jersey

I’d like to know which cities in New Jersey had Slovak communities in the 1890s. I am trying to determine where my great grandmother (Anna Konkol from Nova Lubovna) and her husband (Josef Kravec, perhaps from Smilno) were living at that time. Their daughter Anna was born in March 1892, and according to both the 1910 and 1920 censuses she was born in New Jersey. Josef died in October 1892, and after that my great grandmother moved to Pennsylvania and married again (my great grandfather). I’ve already asked the NJ State Archives to search for the child’s birth record and Josef’s death record in Newark and Passaic, but no luck. My thought now is to write to Slovak churches that were established in NJ by the 1890s. Any information will be welcomed!