The puck bounced weird in the corner in a way he wasn’t expecting. He looked over his shoulder because that’s what everyone does when they go into a corner. That’s not indicative of intent to injure.
I'm guessing you've been on the ice in an average month more than I have in a year, so I accept you've got experience I don't. On the other hand, the fact that he looked over his shoulder as a typical act (gauge the pursuit, see where his help was) doesn't mean he didn't use the information to elbow intentionally. If you watch again, after the glance back, he has no issue tracking the puck, or any abrupt change of his skating or reaching motion because of the carom of the puck.
In my eyes what sets that play apart from an unintentional elbow is the angle of the motion. The act of digging the puck (straight to support) the way he was, then just as quickly yanking the elbow back (acknowledging it might have been in preparation to the impending hit), he was less likely to be successful with the angle of his arm motion. We almost always see that as a mostly level dig at the puck. It was a sneaky, veteran move with just enough plausibility to allow him to say it wasn't intentional. As we used to say, accidentally on purpose.
I will say you've made me overthink it (!), and I'm less sure than I was in the immediate aftermath.
