Willow's words entered Snake's ears the same time the arrow pierced Oliver's shoulder, Snake reached out to grab Oliver before he falls to the ground. Snake turned towards the direction the arrow was fired and spotted the other native, the other native made a sound mimicking a bird which is a signal for his people to come and join the hunt. Snake wanted to run across the bridge and stab the native badly, but right now his priority is set on stopping Oliver's bleeding. He could not remove the arrow as it would just worsen the bleeding, Oliver requires medical attention but they could not turn back, the slavers are probably at the village by now. He handed his spear to Willow. Luckily or not, Oliver was a kid so Snake could lift him with ease, he did so and exclaimed to the other slaves, "We run, now!"