Fernando,
In replay - especially in slow motion - the primary force of the contact was with defenders shoulder in to the ball carrier's body. There may have been some contact between the helmets, but the defender did not lead with his head, and, in fact, it appears that he actually turned his own head slightly in an effort to avoid making contact with his helmet. And an upright ball carrier is not a 'defenseless' player. So, any this is just incidental helmet-to-helmet contact.
This really does not reach the level of "targeting."
But, again, if these defenders will learn to tackle the ball carrier (wrap their arms around them and bring them to the ground), instead of just trying to hit them as hard as they can, almost all targeting calls will disappear.
Robert