1) you can file complaint of defamation against your worker for having filed false complaint before police
2) you can also sue him for damages
3)Lodging of a false FIR/complaint is punishable under IPC. Such an informant/ complainant can be proceeded against under section 182 IPC or under section 211 of IPC by the police.
4)Section 211 of IPC states whoever, with intent to cause injury to any person, institutes or causes to be instituted any criminal proceeding against that person, or falsely charges any person with having committed an offence, knowing that there is no just or lawful ground for such proceeding or charge against that person, shall be punished with imprisonment of either description for a term, which may extend to seven years, and shall also be liable to fine.