Man, that pose is hard. I've been trying it randomly, daily, for about a month and just now am able to hold it for ~5-10 minutes. And I'm in shape. It probably got the camera guy ready and flipped upside-down, trying to get a good shot in the 2 seconds it would have, before falling over. Hell, its legs are probably at that angle because it's already mid-collapse. A proper sirsasana is supposed to look like this.