Hi, I am Myra's cousin - also descended from Johan Welter and Christiana Hammer. I have an Uncle Charles Welter and that could be another clue to a connection with Joseph. One reason the Welter families settled in the midwest is that they were farmers in Germany and Indiana was good farmland. I suspect there are other factors but haven't found those yet.
The family became German Reformed "at the time of Luther", according to a now-deceased relative. She said they left Germany in the mid 1800s to protect their sons from the ever-constant wars and rebellions. I found a few church records in a German Evangelical German Church in Marion County, Indiana.
There is a German Genealogy seminar in Glendale, CA October 14, 2000. If any of you researchers want details, email me personally.