Im confused, if they go to the past dungeon and the people that should die, suddenly not d...

they're only a fragment of the memory/book. they died in the real world even if they are saved in that dungeon. the dead cannot comeback well that's just my guess

I see, thank youu

im actually also curious because they said the party was killed, but in actuality they were regarded as missing because no traces of them were found after the battle. i think there's a very small chance that something different would happen once mc clears this hero dungeon.