Turns out they were demonic scoundrels!
Bai clan leader watches the smoke image of Fang Yuan’s group reach the end of the cave. She sees no spirit spring and decides more time is needed. She puts the smoke away and calls in an investigative Gu Master, who reports that he has captured a Tie clan Gu Master. She frowns slightly, since Tie clan is a huge powerhouse that not even ten Bai clans could match, and she blames him for not killing the man secretly in the woods. ch. 220
The investigative Gu Master says he found the man heavily injured while searching for Gu Yue remnants. After healing him, he learned that Qing Mao mountain’s three clans were completely wiped out, that a mysterious demonic Gu Master escaped, and that Tie clan mobilized to pursue the demonic Gu Masters. Bai clan leader thinks of Fang Yuan and Bai Ning Bing but doubts them, remembering Fang Yuan crying at the banquet. The token taken from the captive proves genuine. She suspects he may have killed a Tie clan Gu Master for it, or may be the demonic Gu Master himself. She orders the captive brought. ch. 220
Tie Dao Ku is forced to his knees and resists, saying he kneels only to heaven and earth, his parents and his clan leader. She sneers that this is great acting and accuses him of being a demonic Gu Master. He spits bloody phlegm, which strikes an invisible wall and falls, and he threatens Bai clan with the revenge of all Tie clan. She answers that Tie clan Gu Masters below rank five move in large numbers and are extremely spirited, while he travels alone in a poor state. His cold sneer freezes. ch. 220
He remembers that nine left Qing Mao mountain and only he remains, a prisoner. Tie Ao Tian, the fourth young master and a contender for clan leader, was blown to bits in an explosion before he could activate a defensive Gu, leaving a palm sized piece of flesh. Others died with countless Gu worms, and of the two survivors, Tie Dao Ku lived because his Gu had turned his skin to bronze, while the other died after falling into a coma. He buried his clansmen under a rock tomb and read the site as almost a hundred charred thunder potatoes buried together, an evil trap. He suspects Fang and Bai, without knowing their names, and swears revenge, since he cannot return empty handed before settling the fourth young master’s death. His injuries bring fever, beasts attack him, and he faints, to wake as Bai clan’s captive. ch. 220
Bai clan leader sees that he answers nothing and does not look fake, and she feels something amiss. When she mentions two Gu Yue clan guests, his dead eyes shine, and he shouts that they must be the demonic Gu Masters. Asked where his companions are, he says they are dead, and he refuses to say where, since he will not let their graves be dug. Her heart sinks, for a demonic Gu Master would not say this. She waves her sleeves, and the smoke shows Fang Yuan gripping Bai Hua and Bai Sheng by the throats, telling Bai clan its young master is in his hands and it must get out. She is dumbstruck, then smashes the table in a rage. She wants to scream that they were demonic scoundrels. ch. 220