I'm pretty sure the images were originally part of an announcement of the contest results on the official website.
As for inclusion on ParagonWiki, it would be up to the individual artists whether or not the images should be uploaded. If they were/are, the page for each image should explicitly state that the images are used by permission of the original artist and they retain all rights to the image. (And a link of some sort to the artist's DeviantArt page, Twitter feed, Facebook page, or some similar thing would probably be nice, too.)