He brought Jing Yunyan to meet Leng Shaoting and Gu Ning simply to help them remember Jing Yunyan's face. After remembering Jing Yunyan's face, they could better stop him from winning a prize.
"I can't promise that they'll agree to team up with you, so the result isn't up to me," said Jing Jining.
Jing Yunyan didn't know Jing Jining's real purpose, and thought that Jing Jining agreed to help him in fear of his father.
"Sure," said Jing Yunyan.
In fact, Jing Yunyan was unwilling to team up with Shangguan Yang's disciples because he disliked them. Even if they hadn't met yet, he was already jealous of them because they and their master were all at a higher level than most cultivators. However, for the best benefits, he had to team up with them so that he was more likely to win a prize.
Although he was stronger than most of the participants in this game, he had strong competitors as well. If he didn't have any sense of crisis, he would fail.