The images may look the same, but their sha1 sums differ.
I created hex dumps and looked at the diff of that, and most of the diff seems to be due to an offset. I have no image experience, so I can't say what is going on here.

One thing that stands out is that according to file metadata, it may be that these were created in rapid succession, and don't really contain any hidden secrets.

Someone with image manipulation/photoshop pls confirm.

Also, chances are this might be April Fools joke, and not an actual challenge. Although I think it would be pretty awesome if its a real challenge disguised as april fools :)