As noted earlier, Alberto Del Rio will be appearing at Triple Mania in Mexico City This Sunday night as a special guest. He will likely be a strong babyface given the strong circumstances surrounding his firing from WWE.
The reason why Del Rio can appear at the show is because his WWE no compete clause does not extend to Mexico. He will not scheduled to wrestle.
The situation with Del Rio and WWE is said to be very acrimonious right now. They don't want him appearing for TNA or the American version of AAA when it airs on the El Rey Network and they are trying to tie him up in a longer non compete. Source are saying that they want him in the type of non compete that Jim Ross. If you recall, Ross was let go last year but was officially done with the company (per his contract) just a couple of weeks ago so Ross was not able to work for another wrestling company until his non compete was over. If WWE did the same with Del Rio then they would have to pay him during that time.