Han XiGuang had been threading on a way to tell Wu Suyi the truth. He was the one who had let the news of HaoRan's scandal all over the world, telling it so the whole people in Beijing, even the rats would know about it. Even if Wu Jun had kept the scandal under control, everyone knew in their mind that HaoRan had killed someone and it was all because of him.
The moment he received the information of the scandal from YueLian, he didn't think much of it and had instead thought it was the best chance to get back after what HaoRan and JingYi did to SuYi.
He had found out everything was a ruse only after the scandal had spread like wildfire. At first Han XiGuang thought to apologize directly to HaoRan but after seeing how the man had almost took his own life, he thought it would be better to come clean with Wu SuYi first.
