I don't know where the uploader got those 'extra' images from, but the lower-size set got exactly the same images and the same amount of images like the high-res set, if the rule is that you can just use pixiv or any other h-artist site to add some 'extra' images on a cg set to REPLACE the previous gallery, than I would had done that on many cg sets galleries.
Just so you know it, I always check the content of cg sets carefully before I upload it.
I've already sended a pm to the vigilante hourssss ago, but they didn't respond. :/