>Name of FATHER?
Not sure if this was shown already. Tried to track it down from Dorothea's side. The only weak point in the tree indeed appears to be "Horst Kasner", or with his mother rather.
Some sources say "unknown", others say it's "Margarethe Drange".
If it were another "Drange", Angela's father & mother would both have had mothers with identical surname. Could be … but a hillarious coincidence then.
The mother-side branch appears to be pretty well documented, not many holes/unknowns.
So if anything, then the link to another family (e.g. Hitler) could possibly come in with Angela's grandmother.
Also Ludwig Marian Kazmierczak was born out of wedlock, which I could imagine might not have been uncomplicated in catholic Poland and that might have affected him ….