I won't be able to help on descendants of Zacharias; I imagine you already have the baptism of Christina on 9 May 1759, d/o Zacharias Ditterer and wife, sponsors "Jacob Wannenmacher and wife, also the parents of Zach. Detterer" at New Goshenhoppen Reformed Congregation, Upper Hanover Township, Montgomery County.
I also don't know the relation of the Michael Tetro (3m over 16, 1 m under 16, 5f) who's listed in Bucks 1790 along with Zacharias, or if the George Titlow (1-3-2) there is a name-goof or a different family.
But I have, from F. W. Waite's "Bucks County Tombstone Inscriptions, Hilltown Township", p. 111: St. Peter's Union Cemetery, old section, Row 35 Dettero Zacharias aged 80y 1726 - 24 Oct 1806 Zum Gedachunms von MARIA Gerirautha Dederersle [Dederer?] [dates on stone] 72y 10m 25d 8 Mar 1744 - 31 Jan 1844
I probably abbreviated the months myself in my notes, but I'm not sure.I don't have any estate or probate info on Zacharias.