Source: The Wrestling Observer Newsletter
According to sources, Triple H reportedly informed Alberto Del Rio to "keep his nose clean" when he called to inform Del Rio that he was fired from WWE. This is taken to mean that Del Rio could have been rehired to the company in about six months after the heat from the backstage incident died down. There is precedence for WWE rehiring wrestlers after letting them go in the past as a disciplinary action. Case in point, Daniel Bryan's firing in 2010 for choking Justin Roberts on TV. However, Del Rio is said to have told Triple H that he had no interest in returning to the WWE.
In addition, the source goes on to say that top stars, including John Cena, Big Show, and Randy Orton spoke to Del Rio and said they would push for him to get rehired because many talents in the locker room took Del Rio's side over his slapping of Cody Barbierri. Del Rio then made it clear to the aforementioned Superstars that he never wants to return.