I don’t think I read the article but heard his interview about it, and it said that kids connected first (she came up to ask him a chemistry question, I think), but then R Moshe approached R Tendler. I presume
– she knew whom she is approaching (what is a chance of meeting a random guy in NYPL and have both fathers on the same beis din?!)
– she mentioned the name to her father in a subtle way.
Why wasn’t she interested in any of the R Moshe’s students? I don’t know. Maybe because R Moshe was not recommending college to them?