The police checked Junhee's identity. Then, the doctor saved Junhee. So, the doctor trusted what the police had written in the wall. In the typical mafia games, the doctor has to choose who he wants to save before the night. There's no time to communicate each other.
One thing I wonder is that this is the first time in 1000+ years Doha as a ghost could enter into a human's body, right? He could not save her previous 18 lives from getting killed by other person (possibly the stepfather evil spirit), because he was just a mere ghost.
He could not save her previous 18 lives from getting killed by other person (possibly the stepfather evil spirit), because he was just a mere ghost.