Your chart: I read that whole thing back when I researched this. As I said, the first name was generally biblical. The middle name was after a family member according to the chart.
Hence the name you should be looking for is Dorothea, if they used the pattern. This info is found under the chart like the one you posted I am posting it for you to read:
Birth/ Baptismal Names
Two names were usually given to a child at birth or baptism. In Germany, the first name - what we often refer to as a given name - was a spiritual name, usually to honor a favorite saint. The spiritual name was often used repeatedly in families.
The second name - what we now would refer to as a middle name - was a secular or call name, and was the name by which the person was known.
One of the most common and heavily used saint’s names for males was “Johann” (with no “s”), and for females, “Johanna” or “Anna”.
Thus, in a hypothetical German family, we might see the male children named:
Johann Heinrich Riepe
Johann Hermann Riepe
Johann Friedrich Riepe
Respectively, these children would be known as Heinrich (Henry), Hermann, and Friedrich
Hope this clarifies what I am saying. When you go looking, look for Dorothea not necessarily Angela.
According to wiki . . . Am going to post both sides just to be complete
Her paternal grandfather, Ludwik Kaźmierczak, He married Merkel's grandmother Margarethe, a German from Berlin. In 1930, they Germanized the Polish name Kaźmierczak to Kasner.
Merkel's maternal grandparents were Willi Jentzsch, and Gertrud Alma née Drange,
So if I understand . . . Angela's middle name, IF they followed tradition should have been Gertrud . . .
So either they did not follow tradition (possible, not probable) then what Q is suggesting is that things are not what they appear. And as you say we are looking for someone whose name is Dorothea?
Did I repeat that back correctly? Lol
Myself for example. Im the 11th (some claimed 14th) with the same first name though the rules posted above werent followed strictly but a lot of family "re-use". Very few ancestors had a name that could be called biblical. Everyone up to and including my father but not me had at least 4 names.