Prior to the game at Luton last night, I did and reacted exactly as you did - listened to the full podcast; thought Stefan handled calmly and brilliantly each and every attempt to accuse City of some level of wrong-doing; and gave Harris credit for responding to the debate in a polite manner.
Now, to read the subsequent Twitter posts that Harris has put into the public domain regarding Stefan's contribution to the discussion, together with (it seems to me) some rather random, unsubstantiated claims about his employment history, has frankly astonished me too.
Harris clearly isn't a full shilling..
You would hope that someone who knows Nick personally will read those tweets and reach out to him today.
Firstly to stop him from committing further libel but more importantly as a welfare check because his behaviour is quite concerning.