My "discovery" centers on nonsensical rubbish on "Bach" in general-deriving from Britanica and Grove mainly (original source "W.F.Bach-Wieland" however)- and on the Koch identities of JS"Bach", Wilhelm Friedmann "Bach" and "Wieland", previously presented and explained in this thread (to everyone but you apparently.)
You may go on focusing your sights in Vienna forever while leaving developments in Lutheran Germany intact...
however
.. an excellent source fully confirms my "theories" (including the above aliases) putting moreover your Forkel's own identity in serious doubt:
http://de.wikisource.org/wiki/Die_Mu..._zur_Gegenwart
...and as for Cocchi-Bach-Bagge and his relations to Mendelsohn family: The question is not if Felix promoted or not Cocchi's ancestor, JSKoch, as from 1823 but how, when and from whom, did the Mendelsohns-long associates of various "Kochs-Bachs", one in particular serving as treasurer of the royal house of France in the meantime-got hold of a specific part of the family owned autographs (the religious part) to then promote Lutheran religion in Prussia (through Forkel getting his "Bach" info from Wieland/Friedman Koch at the same time with "lexikon Koch" (turned roman catholic in the meantime as "Wilhelm Friedman Bach") publishing his Lexicon.
First musicologists "Forkel" and "Koch" were, most propably, the same person.
and, btw, if you are unable to follow thru, raise the matter to someone else!
Good day.