Who betrayed Ren Amamiya?

Could you please elaborate on the circumstances surrounding the betrayal of Ren Amamiya? Who stands accused of this betrayal, and what evidence has been presented to support these allegations? Were there any warning signs or red flags that should have been noticed prior to the betrayal occurring? Additionally, how has this betrayal impacted Ren Amamiya personally, professionally, or both? Finally, what steps have been taken to address this betrayal and prevent similar situations from occurring in the future?