That's not a bad headcanon. The Gauntlet can cancel/undo a previous use of the Stones, but they can't directly undo the side effects of the Stones themselves. An injury or death caused by Gauntlet activation can't be fixed unless the "Wish" was specifically about causing that injury or death, so Hulk's arm can't be un-withered, Tony or Nat can't be resurrected, etc.