Scioscia isn't being a gentleman, he's being a good manager: he isn't going to embarass the officials even more than they already should by piling on.
Obviously, the crucial thing no one here has (I assume) is audio or transcript of what was or was not said. We can look at the hand signals 'til the cows come home, but they might be moot if the ump said anything that either reinforced Paul's belief the inning was over or clued AJ in that it might not be. Or, if anything he said contradicted what he did physically with the arm and hand gestures.
But, if speculation is the rule of the day:
IMO, and it's only that, I think AJ accepted the out and began to walk when it suddenly occurred to him that a) it was a low pitch and close to being in the dirt, and that b) Paul never tagged him. When he realized that, I think he turns around and realizes the opportunity. If he's going on any act or word of the ump's, it must have contradicted something else the ump said or did.
I say this because, in my thinking, Paul is a veteran enough guy (don't know him at all as a fan, but he's been arond and the Fox crew mentioned he's writing a book on calling pitches) that he wouldn't have missed a simple thing like tagging on a dropped 3rd strike or ball in the dirt if he had had any reason to believe the play hadn't ended. Yes, a "brain fart" is possible and he simply didn't do it, but he seemed to be doing it pretty routinely all night, so I would think that if he at all thought this was a situation warranting a tag, he would've done it.
Perhaps he should've done it anyway, "just to be safe", but at that point I think you're almost arguing that a catcher in the majors should just be tagging every single strikeout victim regardless, no matter where the ball's located, "just to be sure."
Maybe you do that for Little Leagues, but I'd think that at the MLB level the officiating should be quality enough that catchers (and batters) shouldn't have to deal with a play like this, where it appears neither player knew exactly what was happening (however AJ figured out there was a chance to run, his postgame comments sounded to me like he acted on some sort of gut instinct, fuelled by a previous incident where he'd been the victim, rather than from any direct indication from Eddings that the play was still on).
Also, I believe Paul (or whomever it was) who stated that it is custom for the officials to indicate (for both the catcher's and batter's sake) if there was no catch on the third strike.
And finally, to me Eddings' postconf comments struck me as weasel-like. When the one reporter brought up the fact that Paul could have avoided all this by simply making the tag, you could almost see Eddings' eyes light up like "yes, oh g*d yes, that's it that's it, that's my story, not my fault, don't blame me!"
My completely speculative guess is that the ump made a half-(censored) call - whether he meant to call it a third strike and out, or a dropped third strike, he either was incomplete or what he motioned and what he said were contradictory, and in the confusion AJ was simply able to capitalize on it, and then the ump did what he thought would cover it up and not look like the idiot he might have actually been at that crucial moment.
As I said, all pure speculation. I guess I have no "dog" or "horse" in the race persay, as my teams are the Pirates and Red Sox, but I am rooting for the Angels' Darin Erstad (as he's a former Husker) and Orlando Cabrera (former Red Sox who Theo shouldn't have dropped in favor of Renteria).
A little discussed item about umpiring is the no-see call. You go by the appearance or the feel of the play. An example: the swipe tag where the back of the glove is toward you and between you and the runner. You try to get the angle, but don't always have it.
This bounce was the same thing. Now the umpire's actions and calls after the swing are critical. And sometimes the actions of the catcher can "sell" the play to the umpire. If there was no call the catcher has to tag or throw to first even in the bigs.