It's even mentioned in the article: "A similar case in 2006 saw a 26-year-old chimeric woman, Lydia Fairchild, almost lose her children after maternity tests required for welfare payments suggested she wasn’t actually their mother."
The legal system sees genetic forensic evidence as very strong. This result shows that we need to be a bit more careful about the samples we used for genetic testing - although this means police procedures for extracting samples are going to get a lot more complicated than a simple cheek swab.
Which is, from the point of view of the test, exactly the same thing. However, it's obvious that "mater semper certa est" ("the mother is always certain"). That is, almost always, apparently...