The Rebbe himself asks this question why it’s mutar to betten a Rebbe. In his sicha of acharon shel Pesach in Taf Shin Yud, he says that this is a chiddush in Chabad which is not seen in any other chassidim, that THE REBBE IS HASHEM HIMSELF ENCLOTHED IN A BODY!!!! (his words: atzmus umehus areingeshtelt in a guf!) And that’s why the Rebbe is not an intermediary to Hashem, since he is Hashem Himself!!!! Now someone needs a lot of explaining to do!! And it ain’t the litvishers!