The pirate points at the duelists
Notice how they stab for the legs and arms? They're not trying to kill each other, and the pistols were such light caliber that unless you hit them in the chest or face, you wouldn't be able to kill each other. It's rather cruel if you think about it.
The fighting gets fiercer, both combatants thrust at each other and swing, despite the fact that the swords have no cutting capacity. Jack mocks the Englishman by imitating his voice and calling for tea. He turns his back and begins impersonating him, the Englishman slashes at jack, yelling out a fierce battle cry, jack sidesteps, trips the man, and smacks his opponents head as he's falling.