It could very well be a EOS Movie prototype. I'm sure they are out there.
As to pricing of the 5D MK III, Nikon Rumors has a price estimate of $3K for the D800, which is where the D700 started. I doubt that a 5D MK III will be far off this price.
Nothing about the pictures looks like a video shoot, no tripods, no stabilization, guy is always looking through the viewfinder, etc. I think stills when I think of a safari.