I never said the heroes destroyed it, please learn to read. Everything else you said, and this, is irrelevant. Your entire argument hinges on the incorrect assumption that Deathwing can only be killed by the Dragon Soul, when we know for a fact that is untrue because we see him impaled on top of Wyrmrest in End Times, proving that he is able to be killed through normal means... If you don't think Galakrond, who is several times his size and would be hopped up on death magic, which we know makes things stronger, wouldn't be able to overpower him do something similar, you're not being logical.
Infracted.