It is worth mentioning that when Shen Zidan originally plotted against the Kuang Family and the Pei Family, the paternity test reports he used only stated that the parties were not biological fathers and sons, without revealing the true corresponding father-son relationships.
For example, Director Kuang only knew he was not Old Man Kuang's son, and Chairman Pei only knew he was not Old Man Pei's son. Anything else remained completely unknown.
Since Old Man Kuang and Old Man Pei never saw the reports, they theoretically knew nothing either.
Chapter 306