Oaths are ephemeral, for most people, especially for players fighting in the game, a sentence is worth less than a piece of jerky, and trying to gain trust by swearing is inherently a move of the weak—Dai Song certainly isn't weak in the ordinary sense, but compared to Bai Jing and Xu Huo, he is a weakling.
A person might be fearless shedding blood for his beliefs, but he doesn't dare to waste the lives of his compatriots in vain; Xu Huo's strength is clearly not on the same level as other Rank-C Players.
Dai Song didn't disguise his face, so his subtle expressions, heartbeat, and pulse indicated that he believed he was speaking the truth.
Some of Bai Jing's people had altered their appearance, some hadn't, but overall, they also believed they were telling the truth.
