No, I understand what you are saying, but prinicpals have no right to censor what is said about the school. And if they have a problem with anything that is said, so long as it is truthful, then maybe they should be doing something about it rather than just stopping people hearing about it. If it does harm the school's reputation it would be on a more factual basis than any opinons people have about schools otherwise, without hearing anything from inside.
Anyway, it is the participants decision whether to apply or not, this should be considered by them as it is one of the conditions of the application. And presumably people wouldn't apply if they aren't willing to write stuff with their school being disclosed. Where is the problem?