Did the Seven Immortals of Jinghai go to North Korea?

I went to Korea. According to the information on the Internet, Sun went to Korea to find relatives after he was released from prison. 1998 Tianjin Jinghai No.1 Middle School Seven Fairy Incident-Sun tricked seven female students in Jinghai No.1 Middle School into drinking pesticides in the dormitory and died. Because the lawyer repeatedly stressed that the evidence in this case was insufficient, Sun could not be found guilty, but after the first and second trials, the court finally ruled that Zu Xiaoxue was sentenced to life imprisonment. However, she only spent 15 years in prison.