I’m not even going to try to address your question but maybe you missed the bit about the damage perhaps emerging years later, depending on how exposed someone was, and that whilst it maybe debilitating/irreparable - leading to permanent disability - it may not in all cases lead to inevitable death in the short term. So ask yourself this question about ANYONE with ANY disability. Does the fact that the proximate cause is known and is deliberately introduced (equivalent to direct violence) make a difference?
(…and on the day Prof Hawking died, many years after his prognosis suggested he would.)
