That's what is at stake here, really.
The question should be whether Reilly is responsible for a lesser infraction being exacerbated into a more egregious one, or whether he intended to commit the more serious infraction.
From video evidence, it seems likely that the former is correct.
If deemed that way, the punishment will be meted out based on the fact that he is responsible for controlling his stick at all times.
A cross-check to the shoulder wouldn't warrant any supplemental discipline at all, but when it rides to the head, intentional or not, it will be.
So, yes, this is precisely what is at stake.