Well, he knows this guy and its a good cause so I can see him having him on, but he's had guests for just a part of a stream before. This would have been an ideal occasion for this procedure.
And he definitely needs to diversify his topics because the end of the Vic case, as you said, can kill his channel. He seems to want to focus on things that specifically interest him, which is good. I dont want to see him go down offering comments on topics he just doesnt give a shit about like so many other channels resort to to maintain channel growth.