An editor at The Hill has verified that it was indeed Jonathan Kaplan on the second segment of the call, who said, “Screw that and Screw him.”
“Thank you for sending the files. There’s no doubt it was Kaplan.”
The interchange was a clear example of the real bias of some in the media, who allow themselves to be played by the GOP. Mike Conallen, the GOP CoS who hacked into the call had revealed that day that “a reporter” gave him the dial in information.
There's a nice line in audio that basically confirms this as a deliberate move, Kaplan saying "Mike? You gonna help me out here?" This guy's next job will probably be at Fox because there's no question about what he did here.