ROB: you are misinformed. The Satmar Rebbe literally saved hundreds if not thousands of Sephardic Jews from assimilation in Argentina by appointing a Satmar Rav there who strengthened Yiddishkeit and fought against assimilation and many of them are now Satmar Chasidim living in NY. (Definitely at least in the hundreds and growing.)
Additionally Satmar was very active in saving Neshomas in EY although I don’t recall the details. I don’t think they made them Satmar but that was never the goal. The goal was to maintain their Yiddishkeit.