"It is enough that his career ends here."
Why should he be let off the hook. It appears he knew what he was doing. He should be prosecuted for malicious prosecution and departure.
True, I would not let Fitzgerald off the hook either. He was prepared to ruin peoples' careers all due to some unverifiable phone conversations, and then when he didn't get that, he was prepared to ruin peoples' careers due to giving inconsistent answers about what did not even occur.