If the principal took it upon himself to deal personally with every instance of a student in a 3,300-student school (according to the jackwagon history teacher berating Kashuv) being "upset", the principal would never get anything done. The principal is responsible to use common sense and discretion. According to Kashuv, those questioning him had never even looked at the tweet(s) in question.
LEO were present. Why would LEO be present? What idea would be conveyed to a minor student, in the absence of his parents, by the presence of LEO?
You don't need to deal with every student, just the one's that had issue with the situation, or seemed the most upset. It happens. But once again, I'd like to stress we're getting one side of the story. You're taking everything the kid has said as fact. I think that's premature.
One thing that stands out to me, is how "aware" this kid seems about his right... and yet he willingly participated in this "interrogation?" The way he's farmed the situation, that just doesn't sit right with me. He says things like "They used very harsh intimidation tactics." By what standard is he applying? That seems like embellishment. He also says "that they tried to intimidate me to incriminate my father." What does that even mean? Incriminate for what? Did he think the they were trying build a case against his father to have him arrested? The kid is using terms he clearly doesn't fully understand. So like I said, I'd prefer to hear the other side of the story, than just Kyle's recollections.