Killer getting knocked out like that puts him on some solid Veteran Scabbard level. Nothing more than that. Even then Zoro managed to get hit by a random scythe, blame himself and faint (it wasn't fair battle anyway). Killer's feats are comparable to Kawamatsu's
Thats Queen leaving Udon, looking clean. If you show me some character doing what he did in such a little amount of time 1vs1 against Big Mom barely using his full capabilities, then i may reconsider, also it would be good to know which character in the series can do a damage comparable to Big Mom tossing you around like crazy.
Even then, Queen wasn't even knocked out, he got stunned at most
Zoro wasn't in a 1vs1, Kaido refers to the whole Worst Generation on his sentences especially after going Hybrid, before 1010 Kaido knew 2 things coming from Zoro, Enma and Oden's aura coming from it.