I'm not sure why his ex wife became a Christian. Probably out of gratitude from being released from the torment of a bad marriage. Also, she probably converted for the sake of their daughter.
I think the whole lawsuit was childish, vindictive, and a waste of everyone's time. I also have a suspicion that had Mr. Newdow had won his verdict, he would have used it as a basis to sue for custody.
Well, if you can argue your young daughter is being "indoctrinated" with Christianity and you are an atheist, you can completely destroy your wife's lifestyle.
As an evangelical, everything we do revolves around other Christians. We go to skating night, special education events, potlucks, picnics, Christian music concerts, coffees, and of course services.
So if he could extend this to bringing her no place a prayer was offered, he could totally divest his wife and daughter of friendship and support.
Newdow and Banning were never married. She became a Christian after they split up.