No knight is not a cheese. You still play out the mechanics. As the knights still spawn but too late to take the orbs. By definition, not a cheese

You are right, the definition of cheese. Cheese is a food derived from milk that is produced in a wide range of flavors, textures, and forms by coagulation of the milk protein casein. It comprises proteins and fat from milk, usually the milk of cows, buffalo, goats, or sheep