Dear Qwerty,
I am not Chabad at all. I have visited for a day in various Chabad Yeshivos and Shuls.
You are way off of normative chareidi outlook if you think Chabad and Christianity are two but yet the same. Almost everyone considers Cabad full Yidden. They count them for a minyan. They break bread with them. We trust their kashrus and shechita, geirus, kiddushin and gittin. I could go on for a thousand words describing how Chabad is functioning within the rest of Klal Yisroel. You don’t need to be a Lubavitcher to say this. Take a look around. It’s a fact. What makes Satmar or Ger or Skver not Christianity?
Secret societies do not come from Christianity. They come from fools who can’t find the truth and push conspiracies forever. They rise and grumble multiple times in each generation and they keep rolling into the next cycle. Jews are not immune from this.
I would post one more line to explain what I stand for. But it would be misconstrued.