My thought when I first heard the details of the encounter was that it read like a Penthouse short story.
I agree with those who suggest that it would be difficult to recall things from that long ago, however it would be possible to recall something like your very first sexual encounter. So I could give her that she may recall something. However, the fine details would not survive. They would likely be embellished over time with details from modern life.
The real question was raised by, I believe, Mark Levin: How did four unrelated people all come to have their stories published by one reporter from the Washington Post when none of them came forward on their own?
“So I could give her that she may recall something.”
Why would you want to give her that, unless you would want to give her that she is being truthful?
It is just as easy to lie about your first sexual encounter than it is to tell the truth. Or, she could be telling the truth about her first sexual encounter but lying that it was Moore.