The first happened in chapter 923, shortly after Luffy arrived in Wano and he got angry over the way Kaido treated the citizens of the country.
I mean we like have 2 Yonkos here and both of them fall here at once will be a big damn jump and the whole situation in the whole world will go different, just imagine 2 Yonkos fall here!!! Now that he got a way to injure Kaido, and considering that Kaido will surely be defeated, Luffy will reach yonko level in the upcoming arcs.
So when you see the story this is not how the things go right here.
Furthermore, outnumbering him and Big Mom didn't guarantee victory for the Supernovas, but we did see their attacks still chipping away at the two Yonko.
The weak Zeus bade his farewell to Nami as he was no longer able to munch on his favorite snack and Hera finished off what was remaining of Zeus.
He may also be far from seriously injuring Kaido, the strongest creature in the world.