Zhu Hongwu respected position and status. He stood behind Liang Yuan because he respected Liang Yuan’s position as the Crown Prince. That was why he was willing to be behind him and let him take the limelight.
But everyone present knew that Zhu Hongwu was the main character as the Great Zhou Empire came to Mount Kunlun.
Zhu Hongwu was the Grand Advisor and was Liang Yuan’s Master. When the both of them met under normal circumstances, Zhu Hongwu did not need to greet Liang Yuan. On the other hand, Liang Yuan greeted Zhu Hongwu.
But now that they came here together, they represented the Great Zhou Empire. Since Liang Yuan was the Crown Prince, Zhu Hongwu allowed him to steal the limelight.