Hired Hand Ventza’s map solution in Kingdom Come: Deliverance 2 – How to find hidden treasure
If you’re coming from the main bandit camp in Apollonia, head south through the rocks, going through the smaller camp (watch out for the Cumans if you’re coming back later), then when the road forks, look for the cave entrance on your left and the big rock on your right. The loot is underneath the rock on the right, below the skull.