My wife's ex husband tricked her into putting him on her daughters birth certificate we just found out?

This man is a violent drug addict that spent ten years abusing her and her children every way he could. Now we found out that he is on her birth certificate and is listed as her biological father, with all the rights that go with that. He doesn't know but if he finds out he will use it to get to her any way he can. We have already had to move, get her her ccw (concealed weapons permit,) put in a security system and have everything unlisted. Now he might have a way to parade into the picture, and that would end very badly. We live in oregon and I just don't know where to find the info. The courts are useless, they told us they are legally bound they can't help us.