From the New Yorker article:
Mark Krasberg, an assistant professor of neurosurgery at the University of New Mexico who was also a member of Kavanaugh and Ramirez’s class at Yale, said Kavanaugh’s college behavior had become a topic of discussion among former Yale students soon after Kavanaugh’s nomination. In one e-mail that Krasberg received in September, the classmate who recalled hearing about the incident with Ramirez alluded to the allegation and wrote that it “would qualify as a sexual assault,” he speculated, “if it’s true.”
https://www.newyorker.com/news/news...rett-kavanaughs-college-years-deborah-ramirez
It seems to me more likely than not that something DID happen, Kavanaugh's categorical denials notwithstanding.
There is also this in the New Yorker article:
A classmate of Ramirez’s, who declined to be identified because of the partisan battle over Kavanaugh’s nomination, said that another student told him about the incident either on the night of the party or in the next day or two. The classmate said that he is “one-hundred-per-cent sure” that he was told at the time that Kavanaugh was the student who exposed himself to Ramirez. He independently recalled many of the same details offered by Ramirez, including that a male student had encouraged Kavanaugh as he exposed himself.