My son called off his wedding a month before the wedding

My 28 year old son just called off his wedding two days ago and kicked his fiancè out the house. She called me in tears begging me to talk to him. I don't know if I should or not because I feel like it's not my business. He broke it off because she went out of her way to find his father and bring his father to their apartment and invite his father to our wedding.

His fiancè has always openly said how she doesn't agree that I raised him away from his father when I got custody of him again and a boy needs a father. His father was 21 when he got me pregnant and I was 14. I lost custody of him because I had some mentally health issues and was impatient and my mom had cancer so she couldn't care for him. I lost custody of him when he was 7 and his father was extremely abusive towards me. He also went against my wishes. I was molested by my dad and I told his dad to not let my father around him and he did it just to spite me which led to my father sexually abusing my son for 3 years. His dad found out and STILL allowed my dad around him and didn't call the police or anything. His dad is just a disgusting human being and his fiancè knew all of this and still kind of shamed me for never letting him see his dad again once I got custody back.

My son has no interest if ever connected with his dad and she knew that. She surprised him with finding his dad and bringing him to their apartment so he could have a father figure. He got mad at kicked his dad out and kicked her out and took her ring and called off the whole wedding. She wants me to talk to him for her and I don't feel like it's my business. He's an adult. Would you try to fix their relationship or leave it up to your child.