Even if TNO got desintegrated, I think the nature of his immortality would always find a way to bring him back.. as I see his 'essence' or whatever it is that keeps him alive (and you cant desintegrate something that doesnt phisically exists) would just crawl to the nearest living person, kill this person and turn the body into his, or something of the like, as such seems to be the way of the curse/blessing of TNO.
Actualy the manual and several references in the game state or suggest that if he is eaten, burned to ashes, ect. He's dead for good.