Yes, Charles sometimes strikes me as someone who suffered from a degree of hubris. Anyway an outcome, where Charles isn't killed, but captured might be slightly better, though it might also postpone the matter, since he still hasn't a male heir, which he needed for many (not all) of his French possessions, but not his imperial ones. Also Burgundy would be in desperate need for a powerful ally, so emperor Frederick III might achieve a marriage without having to grant any crown (unless he indirectly wants to aggrandize his dynasty, but then it would something like king of Frisia/Friesland or Brabant and not Lotharingia or Burgundy).
Also the funds required to either ransom their duke or continue the struggle, will make for an increasingly displeased Estates General. Even IOTL when duchess Mary the Rich succeeded her father, she was basically forced to accept certain demands from the Estates (even though the all accepted her as their duchess).