It doesent help if he has a split second reaction like goalies do if you cant track the puck.
Before he managed to get his eye where the puck was, it was already across the bar, hence none would be able to react any differently, he couldnt even try to throw the stick, it would only hit the net and puck would already been in the net.
I've played in goal for 19 years (i'm 24) And i can say that not a single goalie there, would have a reaction that would benefit the situation if he lost track of the puck, which is infact something all goalies would do in that situation.
Trained or not, it doesent change the fact that the puck was across the bars, so how do you expect him to react in time? He lost track of the puck, this seems to be taken very lightly on.
If you have played hockey you know the speed on a puck, and how small it is. If you lose track of it, you're gonna have a hell of a time finding it, especially if it gets an odd redirection on the boards.
Your brain works on predicting where objects are going, thats how you can track pucks.
But in this case it bounced off the boards and changed direction(and it was going around the boards in the beginning like any puck would) so the brain has to recalibrate and try to find the puck again.