One, the women were far from litigious (depends on your definition of course but to me taking a year and using everything from humor to begging in an attempt to resolve the case without going to litigation is the opposite of litigious).

Two, they did not have the resources to sue the posters - unless I misunderstood the article, Google's legal firm is representing them for free because Google wants to have control over any legal precedents that affect their ability to index non-moderated online forums.