debt collector calls company re Notice to public

Hi, I recently got a call from someone who call himself an employee of a known newspaper company telling me that a lawyer had paid them to publish a Notice to public that our former employee is no longer connected with our company and that the former employee has a record of violation of article 315-318 (which he said is estafa and swindling) and under investigation in NBI. He told me that it would be unfair to our us not to know about that, he then gave me the number of the lawyer, in case the said former employee would wish to negotiate. And I was completely surprised since as much as I know, no one is allowed to pay for publishing of such notice except for the employer himself. I did asked my supervisor (I'm a HR Assistant by the way), and she said she do not know anything about that. What makes me more concerned is that since our company is a real estate, some of our clients will probably worry if that person has been involved with our credit and collection department . So I tried to contact the HR of the said newpaper company and confirmed that they don't have any employee with such name and they wouldn't allow publication of such notice if it came from anybody aside from the employer himself. After that, I called the lawyer's number to ask him about that. He said that guy from the newspaper company had phoned him telling him that the company confirmed that the guy is no longer connected with us, which then made me doubt that he's not a lawyer because he should be aware that news paper companies have publishing policies. This deception is quiet distressing since this could put our company in jeopardy since we never had anything to do with that (except confirming that the guy is no longer connected with us) and they lied about the whole publishing stuff.I'm definitely sure that this is a collection agency for credit card. Any advice on how can we handle this matter? Thank you