Since you have been here for more than five years, it’s so stupid to take that crappy test. Just provide more evidence to demonstrate the high level of your English proficiency, such as more reference letters from your co-workers, classmates, supervisors, more of your publications plus a statement for waiving the request of an English test. This is enough.
You will feel more confident to do this if you would like to read the information in the following link. But you don’t need hire a lawyer, just do it on your own.
http://immigration.wenxuecity.com/BBSView.php?SubID=jndymzl&MsgID=26
Good luck