One problem, in Mr. Oppenheim’s view, was the lack of on-the-record, on-camera interviews.

“We repeatedly made clear to Ronan and Rich McHugh the standard for publication is we needed at least one credible on-the-record victim or witness of misconduct,” Mr. Oppenheim said. “And we never met that threshold while Ronan was reporting for us.”

Mr. Oppenheim added that the day before the planned trip, Mr. Farrow had asked to pursue the story for another outlet.

“Ronan reached out to us and said: ‘I want to get this out now. I have a magazine that’s willing to do it. Will you be O.K. if I take the reporting to this magazine?’” Mr. Oppenheim said. “And we granted him permission to do so.”

Soon after that mid-August conversation, however, Mr. Farrow, whom NBC described as a nonexclusive contributor, requested the use of an NBC camera crew for the interview in Los Angeles. That request seemed to suggest that he was open to staying on the story for the network. Mr. Oppenheim shot down the request, severing the network’s relationship with the reporter.

Mr. Oppenheim recalled the conversation: “We said: ‘You’ve asked for permission to go elsewhere. You can’t use an NBC camera crew for another outlet. You can do whatever you want to do. And you don’t work for us.’”

Mr. Farrow implied that the network had mishandled his work during an appearance on Rachel Maddow’s MSNBC program that aired shortly after the publication of his first Weinstein article. “I walked into the door at The New Yorker with an explosively reportable piece that should have been public earlier,” he said.

On Twitter last fall, Mr. Farrow praised Mr. McHugh, saying he had “refused to bow to pressure to stop, through numerous shoots, even when it meant risking his job.” He also called him an “unsung hero of this entire story.”