@NP,
“That has not happened in this case and therefore contradicts normative Halachic process. ”
I fail to see the logic in that.
“Would you accept an argument based on a different Chazal that would deny that Moshiach is coming altogether? ”
I wouldn’t, because Halacha as brought in Rambam clearly doesn’t hold like that Deah.
As for the organ playing in Shul etc, I think you should come up with more rational arguments.
All of your arguments are based on the myth that somewhere in Halacha it says that Moshiach cannot be min hameisim, or have an early Techiya. To answer that with “well the Gedolim didn’t say he could be” I’m not aware of which Godol spoke or wrote about these inyanim “Lepilpula b’alma” not in connection to Lubavitch or the Rebbe.