I believe you care correct about Luddendorf. That was the narrative outlined in 1924: The Year That Made Hitler, if Peter Ross Range is to be believed.
However, don't believe the story about Luddendorf is correct, just because you've read it in another secondary source. The level of doubt about the first mention should stay exactly the same as long as nobody has done some background checking.
B) Strawmans are awesome. Don't dare to criticise my strawman. I'm an artist!
C) Yes, adding more reading material is always nice, and none of my comments was supposed to discredit that. Thanks for adding it.
D) Still, don't increase your hopes because you've read another secondary source.