ujm, we discussed this shidduch story here. In the 2nd hand version I heard, possibly she approached him for “help with chemistry”, if I remember correctly. This does not contradict tht he was coming there for a reason, of course 🙂 Apparently, after they already met, R Moshe approached his Beit din haver R Tendler Senior and he approached the son. My deduction was that Miss Feinstein hinted that to her father somehow …
Whatever it is, Avira who does not seem have researched this topic seems to be stuck in the stira that R Tendler is a Zionist and R Moshe is not, therefore some great tragedy might have occurred. Is it maybe possible that R Moshe was OK with a S-I-L that holds different opinions from the Rav himself?!