I second DrewDad. Unions have the power to straighten this stuff out. Are you a member of a protected group? That could help for a discrimination claim.
Why did the administration discriminate? --Probably because they thought they could get away with it. Why did they call you unprofessional for complaining and naming names? --Probably because they think they can get away with it.
Alternatively, people say, "If you want to get called, kiss-a-da-buttza." Nobody likes to get yammered into favoring the yammerer. Threatening works if you have the power to follow through.
Good luck.
Sal