Your sister needs to call the local bar association and ask for their lawyer referral service. She may have both a Federal WC matter, as well as several civil causes of action. The Los Angeles County Bar Association may be able to make some good referrals. Good luck.
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.