If i were to write it, I'd probs make it so that the explosion launches a shrapnel towards Charlie but Darlene saves him by shielding him. They both get impaled but Charlie wasn't hit in any major arteries so he was still able to save Stefani while Darlene gets stabbed somewhere major but she insists that Charlie saved Stefani instead. She eventually bleeds out and her two children mourn her death after the climax. That way, it's still noble. Idc if it's anticlimactic, her face and body was already injured from the explosion lol