#1. Pretend like nothing happened
Hey, the headline says "could return", not "should."
There's simply the distinct possibility that AJ Styles pops on RAW tomorrow night, we get plenty of "we haven't seen him since WrestleMania!" remarks from the announce team, and out he comes to either cut a promo or confront someone else on the roster. Sure, they could make some references to him being buried alive, even question how he's in any shape to be out there so soon.
But, chances are, all those questions will probably be ignored once we get a firm idea of what AJ's next program is going to be.
Now, at first glance, this might seem like lazy storytelling on WWE's part - or lazy writing on my part, take your pick - and it probably would be. But, PTSD (which Styles would clearly have to be suffering from if this had happened to him outside the context of WWE television - if he had even survived) isn't always an immediate symptom to a traumatic event like that.
When you add to the fact that his two best friends in the world have been fired from the company, and it's possible that Styles could simply be repressing his feelings about all of this at the moment.
It's not to say that his PTSD can't come rearing its ugly head back into his life - think of how it affected Tony Stark following The Avengers and in Iron Man 3 - and you could be working with a very thoughtful way to handle this type of situation in a wrestling context.
Or, maybe being buried alive by The Undertaker turned him into a vampire or something. I dunno. It's wrestling. There's a 50/50 chance it'll be something ridiculous.,