Canon 7D mirror box filmed at 10,000fps

I asked this question on the YouTube page, but maybe I’ll have better luck here:

I’m sure I’m making an obvious mistake here, but it’s killing me 🙂

At 4:20 he explains how the top of the picture is “older” than the bottom, due to the way the shutter leaves work. Then at 4:28 he further explains that this is in fact reversed due to the way lenses invert the image, i.e. the bottom of the picture will be “older”.

So why is the shadow of the cork, which is lower in the frame and therefore should be “older”, actually younger (i.e. it happens later in time than the image of the cork itself, which has only just left the bottle?