I will say that it is at least dramatized. I would not be shocked if she shed a tear for the camera more than out of pain. It's not hard to do, easy tricks of the trade and very convincing.
However, that cock is thick enough to stretch some vaginas to a tear-jerking state. So if it is real I would be the first to concede. There is no way to l know, but my opinion is that it is MOSTLY acting. It seems that Napier specializes in these "too big, and it hurts" vids where he plays the gentle giant.
I think all of these kind of vids are more of a dramatization. It really is a thick cock, and it really is stretching, but I doubt the sincerity of stretching to tears.
I think it is more likely that they ARE "paying these girls to cry and act like they can't take a dick," rather than pay them to submit to serious pain. The truth is probably somewhere in between.