Public disruption is one thing, but presuming some sort of berserker behavior “might” happen is just indefensible ignorance. The captain should have just stuck to the fact that the girl was howling and moaning and being disruptive to everyone. That was enough to stop the flight. It’s hard enough for people to deal with special needs children without having to deal with free-floating imaginary histrionic fear-mongerings about them.
Howling and moaning isn’t exactly a threat.