She is no more entitled to quit work than he is. They are divorced and both have an obligation to support their children. If she feels that strongly about the need to be home with the children, then perhaps she might consider some financial sacrifices on her part to enable her to do so. He should not be required to finance her decision, particularly when it appears to be entirely inconsistent with how they raised the children together during the marriage.
If you click on the link you will find a link to the court decision. That tells much more of the story than this article. The mother did make major financial sacrifices to be home with her children. Her income went from 250K to 32K. The weeks that she doesnt have the kids she is still active in their lives in a way that the father is not when she has custody. I dont think that speaks ill of the father, but the court recognized that it was in the children's best interest to have the mother continue her greater involvement.
She is still looking for part time work. I dont know Wisconsin. Maybe this is a rural area and part time work hard to find? It is all spelled out in the court document.
The children were 5, 7 and 9 when this started. I dont have any criticism of her for feeling the best use of her time was being a full time mother to them. I look at this from the standpoint of the kids. What little girl wants to know her father went to court to force her mother to be less available to her (he argued the nanny was good enough).