Contact the best workers' comp lawyer you can find. There are plenty in San Diego. Also, your son is likely protected by the California law prohibiting discrimination and retaliation against employees with disabilities. Find the best plaintiffs' lawyer specializing in these cases. Your son is also likely covered by the California Family Rights Act, if the employer has over 50 employees. These laws provide powerful protection, and can present the employer with the spectre of millions in potential liability exposure if your son has been mistreated. The key is getting the best lawyer specializing in this area of law. The workers comp aspect of this is its own specialty, and will likely be a different lawyer. Retain counsel, the sooner the better. Good luck to you and your son.
It sounds like you should've hired a competent Worker's Compensation attorney yesterday. It is not too late to file your case. Contact an attorney in the San Diego area from this site or from The California applicants attorneys Association CAAA.org
A Certified Specialist in WC is probably Bubba's best plan.
We offer general concepts, but you should give ALL your facts to a licensed Attorney in your state before you RELY upon any legal advice.
Have your son call my office if he wants an attorney. I'm a certified specialist in workers' compensation in north San Diego County. I will set up an appointment if it looks like I can help him. My phone number is 760-433-9009.
Any person who makes or causes to be made any knowingly false or fraudeulent material statement or material represetation for the purpose of objtaining or denying wokres' compensation benefits or payments is guilty of a felony.