One resource that you did not mention is a will. My husband's gg grandfather, 1824-1889, left money in gold to some of his sisters in Neunkirchen, B-W, Germany. From those names and location I was able to greatly expand the family tree because the German family records were available online. While this is a very different location from what you are searching, I suggest that you rule out the possibility of a useful will.

Roberta Jaffer
Massachusetts