Re: kamae problem
To me the point isn't so much which hanmi is 'right', but more that if you are so very convinced your teacher is 'wrong' about such a fundamental thing as posture, why the heck do you want them to be your teacher?
If you don't want to learn what the teacher is teaching, don't take their class... ??
If someone like that is in your class, I'd probably kind of ignore it, personally. As someone else said, there are probably others in the class who would LOVE to have more personal attention and help instead.