Hml – as difficult as this may be to hear, performing miracles is not a proof of someone’s authenticity or correctness. We find chumash openly telling us so – כִּֽי־יָק֤וּם בְּקִרְבְּךָ֙ נָבִ֔יא א֖וֹ חֹלֵ֣ם חֲל֑וֹם וְנָתַ֥ן אֵלֶ֛יךָ א֖וֹת א֥וֹ מוֹפֵֽת (devorim 13:2). If someone tells me that they or their father in law are the essence of god wrapped in a body and their followers say that their leader runs the world, all the miracles in the world will not convince me otherwise. Miracles can be from the sitra achra as well.
AAQ – i too am troubled by the insularity; they seem to be much more open to the likes of steinsaltz, because he had some ancillary chabad affiliation, than gedolei yisroel.
Mesivta – the gemara says “he’alu mibavel”, not stam that they were mishtamesh with them, which I think means that they “elevated” the names from there. It’s drush but it’s meduyak.