If parts of the ACLU's statement vanished, I'm not sure what the issue is. Being an organization and not an individual, they are speaking for their group and some internal discussion for how they represent themselves is reasonable.
Overall, I agree that shouting down speakers that students disagree with needs be stopped by the university. If students want to protest outside the event, by all means, but there is value in debate and discussion. The school also needs to be responsible in bringing in speakers with substance and not just trolls.