I'm sorry you tried to do what was right and got a slap in the face! You've got some great advice given here.
Where I live if you call the cops, your name will be in the paper, something about being able to 'face your accuser', so no worry if they come to your door, the whole town's gonna know you called anyways.
I hope you have luck with the media or childrens services. Bless you for trying to help.