it makes no sense for roger/garp to beat xebec/prime wb/meme/kaido in a 2v4.
since xebec was the captain with the others under his wing, it must mean xebec >= prime wb, and prime wb>=roger=garp. So already it's not looking good for roger/garp, then you add in meme and kaido...
so for this to make sense, either it wasn't actually a 2v4 or wb wasn't at his peak when he was with xebec, meaning:
roger=garp=xebec>wb>meme>kaido