While Yi Chen was discovering hidden truths, Zi Han was on his way home when his mother intercepted him. She wanted to have a serious conversation with him in the absence of his grandfather.
That's because knowing her father he would probably freak out and go knocking on each of the suspects' doors. His motto when it came to his family has always been to shoot on sight and ask questions later.
She didn't want to scare the prey and have them retreat into their holes. If that happens then they won't be easy to catch later.
It was for this reason that she sent secretary K to pick him up instead of Old Lu. Because what they were about to discuss was extremely sensitive she directly flew him to the Han warship with its guns still pointed at Capital Star. Zi Han who hadn't seen the warship named after him before had his face glued to the cruiser's window with sparkly eyes making secretary K chuckle in amusement.