Someone I met said that as a child they remembered meeting JRR Tolkien at a signing event in New York City in the early 70s.

I think the evidence seems to be fairly clear that Tolkien never visited the US. My guess is that they're probably confusing this with a book signing Christopher Tolkien did for the Silmarillion release. I do not know if such an event happened, but I think it's a lot more plausible.

Did Christopher Tolkien do a book signing event in new york city for the release of the Silmarillion? And if not was there a different event they could be confusing this with?