If you visit the LDS site, you will find a bit of confusion compared to your data.It has the David Yokel (sic) (1659-?) marriage to Susanna Heydrick (1696-?), with a son Christoph (~1717-?).Christoph's wife was rendered as Maria Schulta (1722-?) This looks like it might be Shultz to me and a confusion with your Christopher 1718-1810. The Jacob / Susanna Schultz marriage you mention was recorded for a son of Christoph b. 1717, but no offspring were indicated.
The Fayette County, IL Yakels, according to the LDS data, descended from a Casper (sic) born 1769 married to an Anna b. 1774. Casper was a son of the Christoph above.Their children Andrew, Mary and Henry ended up in IL, and married into a lot of families.
Do you have amy insight into the origin of these three Yakels?