No, obviously it is not.  He performed no work on the property or your behalf that would allow him to file such a lien.  And I think that he knows it becuase if he signs the papers before a notary "verifying" that the work was done then he would be committing fraud and possibly perjury.  I might speak with a lawyer about a flat fee for sending a letter regarding the "bill."  It will be worth it in the end should you have to hire an attorney to fight the lien.  Good luck.