Baptism of a minor without parents concent. Help...

So, I'll try to make this shortish. My wife and I raise our daughter(8yrs old) outside of church and religion. She's never been to church or knows Jesus other then it's a name. My father and his girlfriend were babysitting our daughter (for the first time) while we were at work. He said she wanted to go to church with him and his girlfriend. She really just wanted to go where his girlfriend goes(they play together and stuff). I was apprehensive and expressed this, I caved and told him to be careful, she's never been to church. So I figured I'd just answer any questions she would have when we get home later. Come to find out, my father and this church baptized her. Full on white gown dunking in a pool of water. She wanted to play in the pool when she saw it. And they told her it's for baptizing. They barely explained anything to her or told her that she would be pushed under water. She's never been to this church or any other. I can't find anything online about this church or even an address. I called the authorities. I've called and talked to multiple churches and this is appalling. I'm in a waiting game now. Any advice is greatly appreciated. Probably going to seek legal help.