"Then I asked him why Prince Yi wanted to investigate you. He said he didn't know the specific reason, but Prince Yi told them to find out what was wrong with him. No matter what was found, we had to report every detail back. He and the person who had already gone back to report confirmed that there was nothing wrong with the Crown Prince. It was all apparently Jiang Yue's fault.
"I've asked him about Prince Yi's whereabouts. He said he should be in Zhanchang County near Jing Yue. He said that after killing the middle-aged couple who raised Prince Yi, Prince Yi went to Zhanchang County. He said he would stay at the Shoulai Inn in this county. His Highness had already sent some people to Jing Yue to see if they could catch Prince Yi."
Jiang Yue and Xue Yan weren't sure that Prince Yi would be found.
If Prince Yi wasn't reborn, it might still be possible. Now that things have changed, they have to stay vigilant. Otherwise, why would he investigate them?