He can tag top tiers, so he is 100% tagging AND hitting Mingo who is merely an high tier. Tagging IS a speed feat, hitting is the step that comes next, but tagging alone already means a lot. Is it more clear now?
Also Kaido cannot dodge every attack Zoro throws at him, he was hit several times in this arc, even without Law assisting in.
This story that the yonko let themselves be hit is headcanon, I could understand drunk Kaido, but that's about it.