FYI, "אדמו"ר אור ישראל מסטאלין זיע"א" was born in תרכ"ט, which made him all of 5 (!) years old at the time of the story. By the way, Reb Hirsh Margolis was the elter zeide of Dov Eliach, mechaber of ",הגאון" and no fan of Chassidim. Funny how these things work.
Source: HebrewBooks, קובץ ביאו"י