The Yiddish phrase itself makes no sense and literally translated means "don't knock me a teakettle". So why should any slang usage of its words taken individually make any sense either? The meaning is not logical. It's a figure of speech.
It was said on the show. Katie said Bobby was there "hocking" his new book and it sounded like hocking, not hawking. Even the closed captioning spelled it "hocking".
Again, yes they did, it was Katie. See above.