Do some soldered components use solder that only melts in temperatures higher than 480 °C?
No, it will be standard solder.  Whatever was used on the rest of the board.  The problem is that all the metal is conducting the heat away too fast. Also, large number of pins will mean that even when the solder melts you have to pull the (now very hot) part off the board, which is not easy.

One solution is to use a coping saw or similar to slice up the jack, and pliers to crush and break the plastic parts.  If you can reduce it to individual pins soldered into holes you should be able to remove them one by one.

The high power hot air guns you get for stripping paint would also get everything hot enough, but might overheat or blow away nearby components if they are not protected somehow.

I also think it should be possible to use hot air and soldering iron to do this, but it would be tricky. You need a large tip to get the heat flowing, and adding more solder can also help transfer heat. Use the hot air to preheat the jack, and surrounding area of the board - ideally from both sides. Use tin foil to protect nearby components from the airflow.