Was this manager wrongly terminated for harassment?

Q: A large corporation fired a general manager because Human Resources received an allegation of sexual harassment by him. The terminated employee alleging the harassment had been fired at the direction of Human Resources six months prior because it was found that she had sent threatening text messages to another company employee. There was no verbal or written disciplinary action taken against the general manager at any time for any offense until he was terminated. He has seven years of documented exemplary service with this company, as well as letters from all but one of his ex-employees stating that at no time was he ever guilty of sexual harassment or mismanagement of any kind. Does he have legal recourse for wrongful termination? – Sandra, Texas