Yes, but for every action, there is an equal and opposite reaction. So at the very least, we know King can withstand whatever level of force he is capable of outputting. So it stands to reason that if his AP is strong enough to push Zoro back like that, then his defensive abilities are on par with his AP, which is above Zoro's. So he fairs better at blocking the attack, but by how much is the question.
Indeed, this is quite a bitter reality that few Zoron fans were ready for, even fewer ready to accept.
That reality being that Oda plucking Zoro from his high-and-mighty, seemingly untouchable status up on the Rooftop down, relegating
him to fighting King gave way to the highly-likely chance that King would show feats that prove he could replicate (or even out-do) much of what Zoro demonstrated.
In this case being Hakai.
As you pointed out, because King demonstrated that he could overpower Zoro, who was able to block Hakai, that indirectly proves that not only can King block Hakai (disproving the notion that Zo-loser is some tier above the other YC1's), but likely block it even better due to him overpowering Zoro as opposed to merely equaling him.