I am thinking more of a Richard III ending “My kingdom for a Horse” (The grotesque amount of money is symbolic) Director and Writer Vince Gilligan, who is Catholic most likely will not allow Walt to go unpunished. And Walt’s demise will ensue after he is stripped of his legacy rendering everything moot(the pile of money). After Walt kills Hank and accidentally kills his own children - kills Lydia and confronts Jesse,he may hesitate and seal his demise and be killed by Skylar. If this tale ultimately is about redemption, then Jesse lives as he and Marie are the only uncorrupted(or redeemed - the money again) human souls left.
Of course those show could be prequels, especially for Saul......