There's a reason he ran from Hakai. While Zoro didn't.
First of all, Hakai and Kamusari are different type of attacks, Big mom used Ikoku many times before and even vs. Kid, Ikoku/Hakoku and Hakai are similar, not Kamusari, secondly Zolo told Luffy to run from Hakai as well, what kind of ZKK argument is this?