Well, could be that no one has posted a reply because no one has what you are asking for. At least I don't. I've seen two post-production related photos, one from the "Chronicles" shoot and one of Kermit Eller in costume standing on front of Don Post Studios, which strongly suggest that the knobs are diamond cut -- I have no doubt you have seen these photos as they are very common. There is kind of a specular pattern to the way the light reflecting off of them is breaking up which seems inconsistent with a smooth cylinder. Keep in mind that even in high resolution they're pretty blurry.
If you are looking for a crystal clear screen-cap that shows diamond knurling I've certainly never seen one. The news was a revelation to me when I first heard it but looking at the photos it makes perfect sense. Since photobucket went phut I don't have a way to post the picture but I've tried to attach the best one to this post.
(edit--looks like Juan beat me to the post, lol, and he is correct)
Dave