Based on the information you provided, I think you should first understand how the labor regulations define your working relationship. If you joined the canteen work by signing an employment contract with the contractor, then your employment relationship should be established with the contractor, not with the factory. Therefore, your employment relationship should be with the contractor and not directly with the big factory. If you want to continue to defend your rights and interests, you should go to the contractor to claim your rights and interests, rather than continue to fight with the big factory.

Additionally, according to the information you provided, the contractor's business license does not match the actual business situation, which is a problem involving the license issue. If you want to defend your rights and interests, you can also report the contractor's business behavior to the relevant authorities. However, this issue may not be directly related to the labor disputes you have suffered, and requires you to analyze the specific situation.

Finally, it is recommended that you consult a professional lawyer to understand your specific situation and the best way to defend your rights.