It was indeed done by an insider.

After explaining everything to Han Yue and the other two, Randy Ling came to Hei Gong's room.
"Commander-in-Chief!" After seeing Randy Ling, a staff member of the medical hall who was busy in the room bowed and greeted him.
"How is Hei Gong doing?"Randy Ling nodded slightly.
"The medicine you prescribed is amazing. The handprint on Mr. Hei's body has completely disappeared." The medical staff responded, "It won't be long before Mr. Hei wakes up!"
"Yeah!"Randy Ling nodded and walked...