Taking your hypothetical example into account, and integrating it into what's going on right now, my reply to the school would be, 'well I'm fully aware that you've had plenty of individuals on campus speaking about how much they like blue balloons, and I've had students ask me to come and speak about red balloons, because they either aren't interested in blue balloons, or they are curious and would like to know what red balloons are like.'
If blue balloons are ok and have a sizable audience, what's wrong with a sizable audience that's interested in red balloons? Are red balloons like peanut butter and for the safety of the few who are 'allergic', only blue balloons are permitted?
Again, if "free speech" only applies in circumstances where you are providing equal voice to a counter group, you aren't talking about free speech.
The problem is just that though. An equal voice is either not being allowed or it's being silenced by using loopholes. The fact it got bad enough that it required an order to try and fix the problem is pretty sad. I guess it could have been presented as equality as well, but they probably didn't want to go that far, considering what some have already brought up in this topic.