This is a textbook case where of amateur sleuthing is a bad idea. We're not all Tsutomu Shimomura.

If there is a criminal (or civil) case, there has been no chain of custody. If you find something like this, don't even touch it, get someone qualified.

Secondly, it seems highly likely the person who created the image is not the person who emplaced it. The use of a VPN is hardly an indicator of evil intent. At least the author did not put any names in their publication.