I am pretty sure Kaido will ask Momo for his name in the next chapter. He will grab him and ask what momos name is.
Back then in the castle, Momo couldnt answer him, cause he was just in tears, weak and scared. But now, Momo will answer him straight away. Kaido was kinda dissapointed of Momo back then, still no idea what this scene should tell us. But this time, he will see the change in Momo.
But i have no idea what this question and the answer means for Kaido.