When Reince Priebus departed from the West Wing in July, after months of rumor and acrimony, he didn’t let the door hit him on the way out. “A president has a right to hit a reset button. I think it’s a good time to hit the reset button,” he told CNN. “I’m always going to be a Trump fan.”

But the graceful exit and months of public silence were very far from the end of the story. On Friday, Priebus testified for hours with lawyers on special counsel Robert Mueller’s team who are probing possible Russia collusion and a host of other matters, including obstruction of justice in Trump’s decision to fire F.B.I. Director James Comey. While Priebus has been careful not to criticize the president openly, sources who have spoken to him say he’s not happy about the way he was treated by Trump and his family. “He was champing at the bit to testify,” a Republican familiar with Priebus’s thinking said. Priebus declined to comment to me about what he told Mueller’s lawyers, but his attorney, William Burck, told Politico that his client “was happy to answer all of their questions.”

According to sources familiar with the matter, the person in Trump’s orbit who may have the most to be worried about in Priebus’s testimony is Jared Kushner. Priebus has knowledge of Kushner’s proximity to the controversial decision to fire Comey during a weekend at Trump’s golf club in Bedminster, New Jersey, in early May, which, hypothetically, is the lynchpin of an obstruction case against the president and his advisers. Trump was accompanied for the weekend by Kushner, Ivanka Trump, and Stephen Miller. At the club, Miller drafted an angry letter to Comey justifying his removal. (White House counsel Don McGahn reportedly told Trump to revise the letter, which people who viewed it likened to a “screed.”) The following Monday, after returning to Washington, Trump told other advisers, including Priebus, of the decision to oust Comey during an Oval Office meeting.

Kushner’s closeness to the discussion of firing Comey continues to be much discussed by current and former Trump administration officials, who see it as one of the main drivers of the administration’s present legal travails. Two sources familiar with the matter told me that prior to Comey’s dismissal, Kushner expressed concern to West Wing officials about the investigation. “He’s all over us,” Kushner told one official in February, according to two sources briefed on the conversation. “He was freaked out about Comey from day one,” one Trump adviser said.

Some in the West Wing were concerned about Kushner's entanglements even before he was a government employee. According to two sources familiar with the matter, transition officials became concerned about meetings that Kushner had helped to set up with representatives from the Chinese insurance giant Anbang and the Qatari Sovereign Wealth Fund to raise hundreds of millions to bail out 666 Fifth Avenue, the debt-laden crown jewel in his family’s real-estate empire. The meetings raise ethical questions given Kushner’s status as a presidential adviser involved in foreign policy. They worried that he could be subject to, as one of them put it, “an influence operation” by foreign governments.

Kushner’s attorney Abbe Lowell declined to comment. On Monday evening I was contacted by Charles Harder in his capacity as a legal representative for Kushner. He, too, declined to comment. (Harder, who has represented Hulk Hogan and Melania Trump, recently severed ties with another client, Harvey Weinstein.) Ty Cobb, a member of Trump’s legal team, who is handling the administration’s response to various legal and federal investigations, e-mailed me to say: “It is disturbing how unsubstantiated and reckless this story is. It combines conclusions arising without foundation with well worn but widely peddled fantasies that other outlets have passed on for months because nothing in it is verifiable except for the long well known fact that Jared and his family were in New Jersey that weekend. Jared has fully cooperated with all investigations since the beginning. He has been demonstrably transparent with the Congress. Jared voluntarily produced documents and even appeared for six hours of well received testimony before investigative bodies. Way out of bounds, here!”