Russell L. King, who is listed on his website as Mr. Iglesias’s lawyer, did not immediately return a request for comment. Sony Music, the singer’s record label, also did not immediately return a request for comment, and a message sent through the singer’s official website went unanswered. The outlets that conducted the investigation, the news site elDiario.es and the television network Univision Noticias, wrote that Mr. Iglesias had not responded to repeated requests for comment.