Step son kicked out of his moms

My husband lives in a different state and wasn't able to see his son often and his baby momma always tried to keep him away. My husband is also a felon so it's harder for him. We have 2 kids together. 11 and 8. Both boys. His son is 14. Well his mom drove him 3 hours here to give him to us because she is mad at him and wants nothing to do with him. She walked in on him in bed with her best friend. Who is in her 40's like her. She called my step son disgusting and a pervert and she doesn't want him anymore. She's still friends with her best friend and me and my husband think she's in love with her honestly... We have sat him down and told him how it's wrong for adults to be attracted to children and he did nothing wrong. He just sighed and started crying about hurting his mom. I said he didn't and she's blaming the wrong person. He doesn't want to report her and refuses to talk about it. He doesn't want to hurt his mom more. We are gonna have him see a counselor. Hopefully this will help him sort out his feelings.