Omarosa Manigault has just revealed the one person she believes could end the reign of President Trump: his personal assistant.

According to Newsweek, Manigault, who has been hyper-critical of the president since she was unceremoniously booted from his administration, appeared on MSNBC’s ‘Hardball’ on Tuesday and opened up about Trump’s secretary, the only person whose testimony she believes could truly damage him.

“One name: Rhona Graff,” the former White House aide told host Chris Matthews during their sit down. “She knows everyone. She knows the role they play. She knows who said what and when. She set up the meetings.”

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“If she is called to testify, that will be the end of Donald Trump,” Manigault explains.

To her point, last week, Trump’s former personal attorney, Michael Cohen, said Graff could corroborate his allegations of financial wrongdoing by his old employer.

Graff reportedly worked for Trump for 30 years and is a senior vice president at the Trump Organization. For many years she was considered the “gatekeeper” as he ran his real estate empire, and even after Trump moved into the White House, Graff has continued to manage the affairs of his business.

But Manigault warns that due to Graff’s unwavering allegiance over the last three decades, even if she is called to testify by Congress, there are no guarantees that she would cooperate with the proceedings.

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“I wouldn’t be surprised if she pled the Fifth,” she said. “It wouldn’t surprise me at all, because she’s been fiercely loyal to the president of the United States.”

When Matthews inquired what else Trump fears (aside from his assistant turning on him), Manigault replied, “I think he’s afraid of failure.”

“And he knows once he’s impeached, that will be the most significant sign that he is truly a failure and that he has been running the biggest, greatest—and perpetuating the greatest fraud on the American people because he was not able, capable or prepared to be president of the United States.”

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