I would recommend some clever editing and maybe a lil Vfx work to take the climax battle between Obi and Vader, and end it with the scene of Vader lifting Obiwan into the air and dragging him through fire.

That way, Obiwan doesn’t win the epic fight between them.

Maybe just snip the scene of Obiwan slicing open his mask. Keep the dialogue but use scenes of Vader with his mask intact and only having breathing problems. Before Vader ultimately drags him through fire after lifting him in the air