Strictly speaking, the Hamano couple has basically nothing to do with the case, at least they have nothing to do with the murder. The worst they could be accused of is perjury and harboring.
Kiyomi Liuli was stunned and confused, "One case, two groups of offenders? What should we do about that?"
"Nothing can be done; the case will fall apart."
"Fall apart?"
"Yes, now that the 'murderer' has turned himself in, the police can only take Koga and the others away for investigation under the pretext of perjury, interference in the search. But these people have a solid resolve, they were already prepared to go to jail, there is nothing to fear. Now, as long as they stick to their story that they made false testimonies just to help the Hamano elderly couple, and together point to the Hamano couple as the murderers, there will be eyewitness testimony and physical evidence both present, and the police will have to submit the case to the prosecution despite themselves.