Filing claims with your airline and the TSA is probably the best you can do.

TSA-approved locks are notorious for not arriving at their destinations. Sometimes, they become jammed in the airline's automated baggage handling equipment and break off. Sometimes, TSOs who remove them in order to conduct inspections neglect to re-attach the lock. And, regrettably, sometimes unscrupulous folks (either at the airlines or TSA) obtain master keys for locks (or remove them by other means) in order to steal. Whether your problem was accidental or intentional is probably impossible to determine.