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Certainly looks to me like there was helmet to helmet contact, but the replays on that are sufficiently inconclusive to call it.
Daniels didn't turn his helmet into the contact, so duty on the defender to somehow avoid it -- I don't believe he did enough to get his own helmet out of the collision path.

Still, a reasonable no-call, and not one I would expect to go ND's way in an ACC reffed game.