After hearing Randy's words, the old man's eyes widen in slight surprise, and then realized that what the young man just said was indeed the case. Since they had been prepared to attack a monster instead of a human, they were all ready with their weapons in their hands to engage the opposition. However, that was no longer needed.
Although he had tried to explain things briefly to his people, they did not listen to him and were instead on their guards against someone that had evidently saved his granddaughter.
Even if he had acknowledged the young man's words, there was no guarantee that his people would do the same, considering their actions from before.
With that in mind, he turned around and then went to discuss something with the people behind him as he displayed a serious expression, seemingly convincing them to drop down their guards.