Having heard Lin Mu's words, Hua San and Hua Wu couldn't really reject them. They were reasonable requests and besides, if Lin Mu and Jing Luo were to go to the royal palace, they would be willingly given an audience with a king.
Their cultivation base gave them the authority to ask for such a thing. Though the only reason why Lin Mu hadn't done, that was because he was unsure if Gu Yao had his spies here as well.
But now that he knew about the situation of the Noon Grass sect and how they have been careful since the start, they reckoned it would be fine. Plus, Lin Mu himself had spied on their records and could tell that the Hong Lin kingdom was still relatively safe.