Reportedly the village elder at the time these objects were made, Barak Obamavic, told the artists "you didn't make those."
Like early man, our Resident is reputed to come out of Africa. Unlike our Recumbent Resident, these early hominids actually have a bit of documentation.
If you Google "Vela Luka - Korcula Island - YouTube" the first one on the list should be one which is 2m56s long (there's an image of a large square white building at the start)--at 2:12 it shows a photo of the opening of the Vela Spila cave.