Ego? Not saying this is the case, but people can take a stand purely on principle. Sometimes people of principle are certainly willing to go to court, occasionally even jail, rather than to submit to something they do not believe in or to authoritarianism.
Admittedly, if violence was actually committed, this is an issue and needs to be proven in court; but with this exception, the complaints do not rise to this level and are a consequence of the modern, liberal, WOKE generation. At the core, these complaints are little more than hurt feelings.
Now Watson is young and has been fully indoctrinated in WOKISM, but it is totally conceivable he could be standing on the principle that what occurred in these sessions was not criminal.
Bottom line, if he maintains his position, this needs to be settled in court. But to the point, is it ego or principle?