[Duffalufagus]

Here is the rule:


83.3 Delayed Off-side – A situation where an attacking player (or players) has preceded the puck across the attacking blue line, but the defending team is in a position to bring the puck back out of its defending zone without any delay or contact with an attacking player, or, the attacking players are in the process of clearing the attacking zone.
If an off-side call is delayed, the Linesman shall drop his arm to nullify the off-side violation and allow play to continue if:
(i) All players of the offending team clear the zone at the same instant (skate contact with the blue line) permitting the attacking players to re-enter the attacking zone, or
(ii) The defending team passes or carries the puck into the neutral zone.
If, during the course of the delayed off-side, any member of the attacking team touches the puck, attempts to gain possession of a loose puck, forces the defending puck carrier further back into his own zone, or who is about to make physical contact with the defending puck carrier, the Linesman shall stop play for the off-side violation.

The bolded is arguable in this case. He dumped it in and the question is: did he attempt to retrieve it before the zone cleared?

Edit: bolded text didn’t copy. Last para of the quoted rule