You'll have to restate what you want, because you suggest that the highlight is not supposed to be dead centre, and it isn't. Dead centre means absolutely positively centered, with no measurable deviation. I clearly see that the highlight overlaps the edge of the pupil, and is not centered. I also see (comparing left and right) the highlight is not offset in the same direction of the two eyes, indicating that either the light source relatively close to the figure, or that the eyes are diverged slightly (as they do in real life.)

Where do you think the highlight should be, given that the light source is infinitely far away, resulting in parallel rays of light reaching the figure.

I tried to find some real photos. Here are a couple that look like your render.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)