For K2 today there is K2 overview map.
It is module + plugin
Plugin collects K2 items (when you use search of it), and pass it to module.
Module shows items on map.
In this case K2 item can have latitude, longitude, icon attributes.
If items in cluster (in the same position), for example events on the same place, there is list of it.
And there is customization for list content and for popup content.
If you will not access to this site I can post some images to explain.
And for your case - I can extend article overview map plugin to have access to your K2 item properties to display map in K2 article with your position (like it is done for simple article). Ie it will be the other call, for example like
And you can add it into your article body to have map.
Or do you need to the other wish. For what reason do you need php access?