I think Eichenwald did some mental math and realized he didn't want to give a yes or a no to that for legal reasons. Trump seems itchy to sue for libel, and his claim did come across as potentially libelous if he couldn't back it up.
But yeah, his behavior was really strange. I think Eichenwald watched tape on Carlson to prepare for the interview and got intimidated. Tucker was clearly in his head. I mean, that guy actually had a file with the words Tucker Carlson Falsehoods printed on it. What the hell is that? He had a prop and he wasn't afraid to use it!
I do hope he is OK. His Twitter meltdown was epic, and well, concerning.