Nice to meet you. What you’re showing me is actually not a bug, but a feature: Map Cluster.
The Map cluster has a max zoom level where it starts grouping images. That value is controlled by you in Theme Options – Google Maps settings http://help.wpestatetheme.org/#googlemaps Modify that number (make it smaller than your map zoom value – in the screenshot).
You can also turn the Cluster off, if that’s what you want.