Imagine this. You have a child. You love your child, and raise her for two years. Your precious child is then kidnapped. You spend years looking for that kid through all legal means, but it seems that hope is lost.
However, after four years, they find your kid. But they say that because she's already in a happy family, you can't have your her back. You have to accept that your child, torn from your home, has to be raised by complete strangers in another country.
This is what the mother is going through. She deserves her child back. It's not a question of what the child wants. As the biological mother, she has the right to choose how to raise her child. The only exception would be if she's unfit to raise a child (ie: put the kid up for adoption, or was abusive, or can't support a child).
Yeah, it'll be upsetting for the kid. But would you want two complete strangers in another country to raise your child? I wouldn't.
And yes. It sucks for the adoptive parents. She was their daughter. But ultimately, she was only there because of human trafficking.
And as for the arguement about the kid not being able to recognize her true parent, and the trauma of leaving her "home" behind... That kid will get older. And eventually, the parents will have to tell the kid that she was adopted. And the parents will have to explain that she had been kidnapped from her home, and when her real mother tried to take her back, her adoptive parents used the power of law to turn the mother away.
IMO, I would think that would screw a kid up a lot more.
And for the people saying the parents were in on the kidnapping... Seriously? There's a ton of kids up for adoption across the whole country. The only reason why you would knowingly adopt a kidnapped child is if you planned to abuse the child. If they find evidence of abuse, lock em away. But until then, I find this highly unlikely.