After looking at the 3D relief of the guy with his pecker in his hand I feel like this was carved in the period immediately preceding the abandonment of the site in pre-history. I base that on the definition of the outlines of the leopards. It appears that initial work had started on giving each of them a 3D view as they are cut in along the margins of the belly and back. Maybe the entire panel would've been a 3D relief had the people been around to complete it.
Something came along and compelled these people to abandon the site or they were killed off by a different group. Very interesting anyway why a group would put so much effort into constructing these sites without the sites being places where they lived. I think I read somewhere that there is no evidence to suggest that anyone ever lived there. They were places where people gathered. I could be wrong though.
I don't think it is necessarily a sign of any tragic upheaval but to me that decline in carving quality indicates that the man wasn't meant to be part of a scene initially.
Perhaps an image of a God or a King.
The leopard-obsessed bunch showed up later and started drawing leopard graffiti around putting in far less effort.
That in itself could represent an invasion but it could also represent young people these days or even aligned additions to the King’s biography for reference.