If your son is saying you didn’t do anything, that is exactly what I was referring to when I said that some kids are not as ruined by what was done to them, as by what the reaction of their “protectors” are. I cannot tell you if calling the police is the answer, though the fact that he knocked him down would make that decision easier for me, but my point was that regardless what someone ELSE does to your son, the part that impacts their future, is whether or not they feel they were defended. Even when they are delusional about what they consider being defended. A different kid may have thought confronting the man was more than adequate defense. If this kid doesn’t, that NEEDS to be dealt with so he can have that peace.
Also, I know lots of doctors, psychologists, teachers, managers etc who stink at their jobs even though they are high ranking. There are those in our Torah world as well. They cover themselves in their learning but they don’t internalize it. It is not just Rabbi’s who do this, it is in every aspect of life.