Source article actually points out that the teacher didn't do anything wrong in the warning, but that the warning was unnecessary and that the survey instrument

Source article actually points out that the teacher didn't do anything wrong in the warning, but that the warning was unnecessary and that the survey instrument was designed to protect students and give them a less risky way to get help than by talking to the police. If the survey designers had communicated with the "administrators" of the survey (the teachers and aides), this whole flap could have been avoided.