I've been in this business for about 5 years, so I'm not completely naive about the politics. But I am feeling bad about having to be a coward in the face of people in power.
Sigh.
So it's not just about the opportunity to improve the department, which is doubtful anyway. It's about what you think of yourself.
A person who declines to tell the whole truth when asked by untrustworthy people is not a coward. A coward would be more someone who picks on someone who can't fight back.
So you're too hard on yourself.