After Batista quit Evolution, and functionally WWE, on-camera in June 2014, the door was still open for "The Animal" to return to the fold. By all accounts, Batista was going to run out for a bit to 'do the movie thing', and dip back in when his media obligations to Guardians of the Galaxy died down. A match with Triple H, who he'd stood up by tersely resigning, had WrestleMania written all over it.
Guardians came out later that summer, and calling it a box office smash is putting it mildly. In all, the movie grossed more than $770 million worldwide, and suddenly, Drax the Destroyer was in high demand. Batista would be cast as assassin Mr. Hinx in the James Bond movie Spectre, which began production in the fall of 2014. A Guardians sequel also loomed large.
With Hollywood blowing up Big Dave's phone, there was little time left for wrestling. The Rock understands how that works.