This is honestly worst than the miscommunication in 9/11. It's just pure apathy. Like imagine getting a call about a potential active shooter. Crazy kid stock piling guns, making crazy social media posts, kicked out of school for fighting, and not putting in the due dillgence of forwarding the complaint to the local field office for investigation.
This is what a complete insitutional failure looks like. Those kids were failed by people entrusted to protect them.
Makes you wonder if they let this shit happen. It really does. If they can't trouble themselves to follow up on a threat like this, what are they doing there?