Hakai was seen from the distance,every one was able to react on this. Kid wasn't able to react on Shanks attack. Now question is was Zolo able tp block all Kings attacks? Answer is no way, he didn't block almost 70% of Kings attacks. Why he should show superior skill to Shanks, if he was at some condition as Kid.
With FS there's no way for Zolo right now be able to block Shanks attack if Shanks himself wouldn't allow him give a chance to block it.