My speculation is because the cursed is not present anymore, maybe mc didn't order the ones in charge if the tomb to kill chairman (which is just dumb) or maybe the chairman is just powerful in a certain sense that the mummification doesn't affect him.why is the chairman not dead? MC was only a few minutes away from dying and turning into a mummy yet from the look of it the chairman has been down there for hours, MC has gotten home and is relaxing and the news reporters are reporting on the tomb so it should have been a long while that he's been trapped...