"If you ever want to get the facts straight about me or the Batman, please write to the original source, myself, for the truth, instead of second guessing"

Bob Kane is suggesting that if anybody ever wishes to know the reality about him or the Batman, they must call him directly rather of counting on second-hand information. He is emphasizing the significance of getting the facts directly and not counting on speculation or rumor. He is likewise implying that he is the initial source of information about himself and the Batman, which he is the only one who can provide the reality. This quote is a pointer that it is necessary to get info from dependable sources and to not depend on reports or speculation. It is also a pointer that Bob Kane is the initial source of information about himself and the Batman, which he is the only one who can provide the truth.