Is Bernie Sanders or Elizabeth Warren lying about whether Bernie said a woman cannot win the presidency in 2020?

I'm reading the story in the NYT, and I'm trying to figure out if it's necessary to say that somebody is lying:

Mr. Sanders vehemently denied making the remark earlier on Monday and accused the Warren campaign staff of “lying” about it, in a statement intended to refute a news report by CNN that relied on anonymous sources. The New York Times and other outlets confirmed the CNN report on Monday afternoon, while the Warren campaign initially declined to comment....

Sanders and Warren had a two-hour meeting in December 2018 in which they talked frankly about how the 2018 race might go, but CNN, this week, decided to put out a story that was very damaging to Sanders, making him sound like a sexist. Sanders had to fly into action and deny everything, and then it became such a big deal that Warren responded:

“Among the topics that came up was what would happen if Democrats nominated a female candidate. I thought a woman could win; he disagreed,” she said. “I have no interest in discussing this private meeting any further because Bernie and I have far more in common than our differences on punditry.”

"I thought a woman could win; he disagreed." That's very starkly put, and I'm skeptical that Bernie would say that a woman cannot win.

I can believe that they talked about the pros and cons of the Democrats going with a female candidate against Trump once again and that Bernie might stress the difficulties a woman would face, while Warren might lean toward the idea that the Democrats need to represent diversity and offer a contrast to Trump.

I can believe what Sanders says he said: He told Warren "that Donald Trump is a sexist, a racist and a liar who would weaponize whatever he could." But I can't believe that Sanders would go to the extreme of taking the position that a woman cannot win.

Nevertheless, in a 2-hour private conversation, in which the 2 power-seekers worked on each other, Sanders could very well have put the words together and announced that a woman cannot win. Didn't he want Warren to stand down and allow him to go forward and run in the left lane?

The existence of the meeting has been public since shortly after it happened in December 2018. The New York Times reported shortly after the meeting took place that Ms. Warren had sought it “as a courtesy,” and that neither party had tried to gain the other’s support or discourage the other from running. But the two senators were the only people in the room, and all reports of what was said had been secondhand....

No one can remember everything that was said in a 2-hour conversation, certainly not verbatim. And in a conversation like that, many things are said hypothetically or for effect, so even a verbatim comment — like "A woman cannot win in 2020" — means very little out of context. That's why it's wrong — speaking of weaponizing whatever you can — to bring that quote/near quote out of the confidential conversation and spring it on the voters.

The real problem here is not that Bernie may have said the words attributed to him, but that Warren's people chose to drag something private into the light for the purpose of making him look like a sexist.