It would be like two brothers to each name a son Alonzo.
You can see, over time, how they went from using Von Vradenburg to Fradenburg (with many variations in between).
They are lovely churches. I seem to recall that the records are in German, rather than Dutch.
http://www.rhinebeckhistory.org/WLC_InfoPage.htm.
I'm not sure whether Kelly's indexes are available on line. Once every several months, I make it to the Clayton Genealogy Library in Houston, which has hard copies, and I look up another family line. I just went on Saturday.
I am getting a subscription to Ancestry for my father for his birthday later this year, so we'll be sure to take a look at the information you've posted.