Anyway.
Yet again, Zoro enters the bubble, the scene cuts away, we see Kuma. We're not told if Kuma left or if it timeskipped to after. The reader gets no context except that he almost died, from the two that saw. Nothing else. Then Zoro says "thanks to your mercy," when Kuma brings it back up in Sabaody providing the missing context from the cutaway. My working theory that you won't be able to change my mind about is that he cut it short.
Him saying that even he would not be able to take it reaffirms my belief in this. Zoro probably took as much as he could near death, and Kuma cut it short early.