What would you do?

I have a coworker who has had a few extra marital affairs at work which is none of my business imo, but I am struggling with something. He is 42 but lies and says he is 52. The reason he does this is because he thinks it makes him harder to find on the sex offender registry. He is a more than one time offender and molested children ages 8 and 6. He also has custody of 3 children one being non verbal and still in diapers at the age of 9. CPS was called and they took the kids away for a week and gave them back. What I'm wondering is if you were in my shoes would you tell the women he is having relationships with? The last one had 2 underage daughters and the current one has young grandchildren. Like I said he lies about his age and does not disclose being on the registry but I feel like if he will be exposed to these kids shouldn't the adults in their life have a right to know? Or should I just continue to stay out of it?