I am trying to desolder a micro connector, and one of the through-holes where the connector legs are soldered is so small that I cannot remove the excess solder. I have tried using flux, adding new solder, and using a manual solder sucker. I have also attempted to clear it with a small pin and a fine-tipped soldering iron, but always with the same result. It is next to the mounting hole, i don't want to overheat the board or damage a plated hole. What do you recommend?

Attached are some photos. Sorry for such a basic question, and thanks in advance.

P.S. Apologies for any errors in my English; I am learning the language.