AITA for reporting my soon to be ex-wife to child support enforcement about her child from her first marriage?

My soon to be ex-wife and I are divorcing because I found out that she was cheating. She had a son from her previous marriage that I treat as one of my own. Her and I haven't been living together since 2020. She has had her ex-husband on child support since their son was 3years old.

In October of 2022 my soon to be ex-wife sent her son from her first marriage to live with me because he really wanted to. In December of 2022 the ex-husband finally had a hearing to have his amount adjusted due to his job change and having a baby with his wife. They set his amount. The soon to be didn't give the court her correct employment and intentionally didn't tell the court that their son hadn't been living with her since October. In January she moved out of state without any of her kids. It's now March and the ex-husband has been paying her child support, but she hasn't had the child. So I called child support enforcement and informed them about this. Am I the asshole for doing this?