As to the resolution of this whole thing, if the Second Circuit does not get involved, it seems to me that BoNY has exactly one avenue left. It will accept the $3 billion payment from Argentina, pay $1.3 billion to NML and $1.7 to exchange bondholders, and ask Argentina for more money. This is not particularly unusual, though normally not practiced at these scales (think of it as a form of bank account garnishment).
Argentina may not even be too opposed to this outcome, because that’s the only way to resolve its problems while saving face and without having to repeal Law 26017. It can certainly afford to pay NML, $1.3 billion is less than 0.3% of its GDP, it probably loses more every year because it’s locked out of international financial markets.