Session 4 Scar Boogeyman

After scar blows up the pokeball several members are standing around the remains trying to figure out who did it etc. right before scar basically admits it was him several people mention that the boogeyman has to admit to it in order to claim it and be cured but i don’t remember that being a rule. Was it always a rule/ Was it added later and I’m just forgetting? If you do know when it was said could you tell me so I can look into it. Tbf it doesn’t matter too much and is probably smart to avoid confusion as partly shown in the videos there was confusion that it was tango as less people knew scar was the boogeyman. I am curious though