Yes, I believe Salinger left it deliberately ambiguous so that the reader gets the reality of a child's vulnerability. Holden/Salinger delivers a warning that perverts are an everpresent danger, sometimes wolves in sheep's clothing so to speak. We get enough to register the warning without actually condemning a teacher who may, indeed, be a good man.
In a way, in writing the book, Salinger behaves like an overprotective mother.
In a way, in writing the book, Salinger behaves like an overprotective mother.