I am expecting that Touya would survive even after the destruction of this 'Seed of Reincarnation", provided that he is still an "Imperfect" Reincarnator to the end.
Touya still being an incomplete reincarnator has been brought up as a point of interest plenty of times. And at this point, i want him to keep being "Senji Touya" rather than "Ishikawa Goemon", and wishing that he didn't actually become a complete one as the mandatory climax cliche.