Kaku fought 2 seraphim at the same time.
S-Hawk is for Zoro, S-Snake would turn him into stone.
And i'm saying one of them was S hawk.
Goofy and Gucci wouldn't just let S bear go lol.
Maybe Lanji did let S shark go.
And as you said, S Snake would one shot him.
So logic dictates that the two seraphs Kaku fought was S hawk and S shark.
At the very least, S hawk is confirmed to be one of the two that kaku fought.
Cause we literally saw kaku chasing s hawk.
Zoro probably got lost for a bit and that's when kaku had to fight s hawk and another seraph.