Not really.... i have been through this matter before and if people make fair comment on their experiances of a certain company it is fine... only thing ppl can try and get you for is defamation and that is where you have to actively seek to tarnish a companies reputation, but if your comment was of an experiance and it shows the company in a negative way it is fair comment... Also there has been reomendations handed down recently where companies should not really be able to claim defmation....
trust me i have been through this shit before and you have nothing to worry about.. so let the guy tell everyone of the experiane he had..