I looked too but also couldn't find anything about his reactions to the show, although I thought I had read something somewhere(maybe in an obit?).
There are so many stories about how the show came to be and the various people proposed, hired, fired, etc. Obviously, some versions conflict. Not everything can be true. One example that differs from this Wikipedia entry is that Styne, certainly by the time he first saw and heard Streisand, didn't want Bancroft who was still in the picture. He then deliberately wrote music he knew Bancroft couldn't sing(and I've always wondered how much could she sing)and she THEN dropped out.
But the connection between Ray Stark and Fanny and Nicky IS absolutely crucial to what emerged. Read elsewhere about the real Fanny and Nicky and you'll find a huge amount of fascinating info that shows just how much the play and film changed the facts. Probably most importantly is that the real Arnstein was MUCH more unsavory than the character onstage/in the film.
His daughter may have looked down/askance on Streisand--and fortunately she didn't get her way with casting--but she sure guaranteed a whitewash of her parental origins.