I don't know if you can have an action for them violating the agreement. However, you should never have signed it. Stealing from an employer is more serious than shoplifting. You could hire a lawyer who may be able to work out a deal for you whereby they won't provide a positive or negative recommendation. I would not give their name on any future employment application.
I dictate answers with Dragon NaturallySpeaking and sometimes I don't catch it when it occasionally types the wrong word such as probably when I mean properly. My answer is for general information purposes (a little more than entertainment) and I do not give legal advice without a personal consultation in New York. I am only licensed to practice law in the State of New York and my answer here pertains to a general question in NY.