Killer likely coated his attack. That was also pre Enma training Zoro. Also used a pointy weapon.
Not to mention the point is it's overrated because people started to claim he can tank Asura or the craziest attacks like Hakai.
Tanking a presumably non coated attack like that from Queen is not a massive feat per se.
Zoro himself should be able to do it if he coated himself considering how good his haki is and that Queen's sword is not a great one most likely.
Will see if Sanji can also coat his Exoskeleton however, or what else he can tank other than that but if I had to bet I would yet not place his durability above King's level, possibly below.