“but they have substituted the Rebbe for HaKodeshBorchu and daven to the Rebbe directly, depend on him for their welfare and parnassah, and have transferred their emunah to him.”
There is a machlokes Rishonim about the permissibility of the tefilla “machnisei rachamim” which is found at the end of selichos. On the surface, it appears as if we are davening to the malachim, or utilizing them as intermediaries between us and hashem, both of which some members of Lubavitch are being accused of by some. And NO, nobody has transferred any Emunah to the Rebbe. They (as do many Chassidim) ask the Rebbe to daven for them. Many people go to the kevarim of tzadikim (even their own parents and grandparents) too. Perhaps many misunderstand exactly what it means to go to a Rebbe or daven at a Kever, especially someone who is not an FFB (as are many members of the Lubavitch community). It doesnt make them an Apikores. It makes them mistaken IF in fact you know what they are thinking, which I dont think anyone can safely say about the overwhelming majority of Lubavitchers around the world.