Why wouldn't she sign? If *all* parties (debtor, jpm, and fdic) agree to a resolution that benefits the *estate* (in this case it's WMI) then she has no choice but to sign.
Commons know it is a stretch to recover anything from the start. So, I doubt anyone of us here is surprised.
I am curious if there is any legal recourse to drag it to the supreme court. But for that to happen, much _wrong-doing-evidences_ would need to be available to support the case.