Thus, the Rebbe has full control over his talmidim, both in life and in death, because he had full control during his life. Thus any person who wants to get close to the rebbe has to first become a talmud of him,
Sorry, I think DY would/should still call you out for Kefirah for saying that, because the issue isn’t about the Kamus of control, but the Eichus – saying that someone has “power” would be the same problem of Shituf (think about it, saying that the Sun has power over those who worship it is outright Avodah Zarah).
Rebbes don’t have any independent power, just as the sun doesn’t have any independent power. All the power that they have is what Hashem gives them.