IANAL and this is only what I would do if it were me.... I would consider seeking a lawyer or paralegal in this matter. For no other reason than the unsettling idea that an organization so unscrupulous, with access to sensitive information, has accused you of offenses for reasons unknown. This whole scenario sounds fishy and I would certainly do what I could to cover my ass if it were me. By slandering you to other workers they have committed defamation of character, which is a tort that you can sue for. At the very least, I would make a sworn (before a justice of the peace, notary public, or the equivalent where you live) affidavit stating that you are aware of the situation at this time and that you deny the accusations made. This should only cost around $50. Try to be as specific as possible as they have probably made an entry on your personnel file with their version of the "facts". Good luck