Liu Zheng also knew about Xu Jun's difficulties. He made a mistake that most men make when they're young, leaving behind a hidden danger, which harmed his daughter. He was the one who felt the most guilty.
He didn't know if he should put all the blame on Xu Jun.
Back then, Xu Jun's situation, and the awkwardness with the Yuan Family, the unfairness and resentment in his heart, with no outlet for it, Tang Ying's appearance was just an opportunity, a strong wife, a Solving Flower, no man can resist the allure of gentleness.
He didn't talk much with Xu Ai about this matter. Now, as they were about to return to the country, they were all part of the same circle, so they couldn't avoid meeting often. Xu Jun would likely seek him out frequently, and it would be impossible not to meet.