Just a few clarifications.
When an article exposed the false line von Dagersheim-Lyher, Brigitte was already in her nineties. I think she died when or shortly after her website ceased to be regularly actualised more than 10 years ago.
Brigitte had payed two professional genealogists to investigate her ancestry. Based on the similarity of information I am convinced that Günther Todd and/or prof. Günther Schweizer used the same source than WAR, the articles of Gerd Wunder.
Dr. Gerd Wunder is very reliable. Mainly a regional historian he is the author of two celebrated books "The Schenk von Stauffenberg, a Family History" and "'Bourgeois' of Hall, Social History of an Imperial Town 1216-1802" (titles freely translated by memory).
And it is quite possible that he knew Margarete's parents but not the name of the husband. Gerd Wund's area of interest is basically southern Germany and a source from Württemberg - a chronicle, a deed, etc. - may well ignore the first name of Johannes Bidembach, a very recent immigrant from Hessen.
So far so good but my problem subsist.
Also by memory (not very trustable) I had the idea that Decker-Hauff was the author of that line and if this correct, Gerd Wunder might have used Decker-Hauff's information in good faith because this last one was only exposed after his death and is his lifetime was a very considerate univerity professor of History with more than 70 works published.
FWIW I do not have "doubts" on Decker-Hauff. His manipulation of sources is public and published in Wikipedia
https://de.wikipedia.org/wiki/Hansmartin_Decker-Hauff
As I said before, Gerd Wunder is reliable and it is possible that a source in Württemberg ignored Johannes' first name. As Johannes came from Hessen, there were not other Bidembach in Württemberg and the chronology is good, so if Margarethe did marry a Bidembach this one was undoubtly Johannes.
Where I see a red flag is in source that ignores Johannes name but knows about a necessarly very short marriage of Johannes Wirttemberger with Walburga von Reischach, a marriage unknown to ES. Walburga was also an immigrant from Hessen and his father died in Ulrichstein wich is less than 20km from Grünberg where Johannes Bidembach came from. From the same area and with the same social status the families shoud know each other.
So if (a big IF) Walburga did marry Johannes Wirttemberger the marriage of a daughter to a Bidembach was something almost expected.
We know why Johannes Bidembach came to Württemberg. The Count of Württemberg was at odds with the emperor and by personal decision, declared the Württemberg protestant. At the time the only important prince protestant was Friedrich, landgrave of Hessen who assisted Württemberg with troops but also with protestant ministers (the thre sons of Johannes Bidenbach were ministers and occupied high places in the hierarchy of Württemberg).
But what I do not see is why an obscure daughter of an officer of low nobility of Hessen is sento to marry a "royal" bastard of Württemberg.
It is possible of course but if I wanted to forge a line in a plausible way, I would create something like those two marriages.
Kind regards,
Francisco
(Portugal)