Would you call CPS/cops

I got the amber alert about a week ago about an infant missing and the "kidnapper" was the father. I put "kidnapper" in quotes because the father's mom had custody of both him and the baby. The father was 26 and autistic and had the mind of a 7 year old and from what I understood he in a way understands the baby is his baby but he's like 7. He just wondered out the house with the baby one day. One of my coworkers saw him and called no one! She said she doesn't believe in calling CPS. As a foster child I told her that's how kids get killed by their parents. And the man has the mind of a 7 YEAR OLD! They're both in danger. The child and the dad have been found since then and all that happened is they were both returned to his mom. He wasn't arrested or anything so I don't understand why she wouldn't have called someone. But a few of my coworkers said they wouldn't have called. I just can't imagine knowing an infant is in danger and not calling anyone. Not just an infant. This poor man who doesn't know any better. So I'm curious. What would you have done if you saw this man and know what happened and that they are looking for him and his baby?

Edit: That's what it said in the Amber alert that the baby was with the father who was mentally 7. He just took the baby in a stroller and wondered off. And when I said he wasn't arrested it wasn't because I thought he should be. Just that they clearly just wanted to get him and the baby home. Not arrest him and throw the baby in foster care.