He takes the secondary lead before the ball is struck; it wasn't a matter of him making a decision, good or bad, that was based on the strike of the ball. There's a reason Mateo would have been out by more- he was making the same decisions before the pitch.
They were getting good secondary leads to both score the tying run in the 9th inning of a game, and to avoid a game ending double play. I mean the scenario cries out to be ready to run on contact. It's not much different than the decision to send Mountcastle in the 8th. It's a decision that didn't work out, but I believe it is the right one.
If the charge is simply they should have reacted to a ball hit 80 mph vs 100, think about the infinitesimal time change that delivers to when the ball the ball is caught. The problem was that Mullins hit it directly in the air to an IF, and not that he hit it at 80 mph vs. 100. Both would have resulted in the same result.
But it is fair for people in good faith to disagree so if you see something in that play that I don't that is your right. But I respectfully disagree based on the above.