Pretty sure he's lying about phoning the White House, just as he lied about having contacted the Columbus, OH local authorities in May of 2015 to report "death threats". He then started screeching about how no one would do anything to save him, and how even more than Zoe and Anita, he was about to be killed at any moment by GribbleGrabble.
Of course when it was discovered that no one had actually contacted the authorities in Ohio about the matter, John did what John does and threw "one of his staffers" under the bus for "contacting the wrong agency". It was probably Warren who fucked up, even though he wasn't working for John at the time, but he's a useful scapegoat so let's hang it on him.
Hey, John, you get what you pay for. If you're not gonna fairly compensate your employees, you've got to expect some slippage.
Not that I believe for a moment any part of John's telling of the story.