These instructions are really incomplete. In addition to the 4 through-hole points mentioned, there are also 2 large ground pads under the connector, and 7 tiny surface-mount pins on the back. Removing this port pretty much requires low-temp (chip-quick) solder or a hot-air rework station. Soldering it back on with only an iron proved quite difficult - hot-air rework station highly recommended. This took me about an hour, and I’ve been soldering (hobby mostly) for the better part of 30 years.
Also, there’s no reason to remove the battery to change the charging port. The motherboard can be removed without removing the battery. And really, the cameras should be disconnected too, rather than leaving them dangling by their ribbon cables.