You’re not giving Conradt enough credit. The man was a District Attorney. There is no reporting on his affectiveness as a District Attorney, but that isn’t a job that is just handed out. As a District Attorney he has more than likely faced a great number of adversarial situations and his experience would have prepared him to stare down this bold face lie.
One could make the argument that as a District Attorney he would know that it is possible to ruin a person's life without ever stepping in a courtroom. He would know that a false accusation, once broadcast on national TV, is as good as fact, and that the accused life is irretrievably ruined.
Who knows? Perhaps there was even a fair measure of self-loathing involved because he had managed to stupidly get himself involved in this horrendous situation.
We will never know. The man is dead.