The meeting that he appeared to be encouraging students to disrupt was for the purpose of dealing with the school's response to tornado damage (presumably on campus from the context). So the "deal" with him not living on campus (again presumably from context) is that he is not really a party to the issues being discussed but has chosen to interject himself into the discussions and in a way to promote confrontation rather than cooperation.
To illustrate in local community terms (the relevance of his residency), if your local government were meeting with the residents of your street to deal with damage from a storm, and the purpose of the meeting was to come up with a plan for a timely completion of repairs and improvements, would you want a community organizer from a neighboring town posting notices accusing your city council of planning to deny claims and obstruct progress and urging your neighbors to get loud and confrontational with lots of documentation and be prepared for a fight? Or would you prefer that he go organize his own community and let you and your neighbors work constructively with the city council reps to come up with a solution? The community organizer from across town has the freedom of speech to go stir up trouble anywhere he likes. You and your neighbors would have no recourse in preventing him from doing so (and I would not suggest that you or your government should be able to prevent him from speaking his mind) as long as he is not trespassing on private property.
Currently I’m living and doing research 2,000 miles away from my institution - at one time I was living in a tent in the Kalahari over 9,000 miles away - but neither then nor now do I feel less a part of the university community than if I was hanging on the quad; my opinion regarding decision-making on campus is just as valid as anyone’s. And what identifies this guy as a “trouble-maker”, the fact that he disagrees with the school administration? I’d be curious why the school is so unwilling to engage in any type of dialog and wants to silence dissent.