While he has not been given a feud to work with since making his return to WWE, Rey Mysterio is very much still a part of the plans for Wrestlemania 30. He was penciled in for a big match against Sin Cara, but management is now looking for a new opponent for him at the pay per view.
Aside from half hearted programs with Sin Cara and Rey Mysterio, Alberto Del Rio really has not been given a full program by WWE to work with since wrestling John Cena at Survivor Series 2013. However, the feeling backstage is that Del Rio is assured a spot at Wrestlemania 30 to draw in the Spanish media.
While the initial plans had him working a match against Sin Cara, WWE may have changed their mind on how to use Rey Mysterio at Wrestlemania 30. There are those within the company that are now leaning towards him working a match against Alberto Del Rio with his mask on the line.
One of the reasons why WWE wants to do a match at Wrestlemania 30 between Rey Mysterio and Sin Cara is that they hope it would generate some interest from the media in Mexico. Management also wants to elevate the Sin Cara character.