Ignis knows all of that. Noct is too selfless despite his outward appearance of being lazy and disinterested. He worries about everyone and everything- which is probably why he is royalty and not Ignis. The only thing Ignis worries about is... something he can't save from the destiny that's rapidly approaching his way.

Noct will never be alone. And if Ignis isn't around, Prompto will be. And Gladio. The only way any one of them would leave Noct's side is if they die.

"Yes... he knocked me out." Ignis doesn't even stop to feel embarrassed before admitting that. He was exhausted from running, fighting, yelling that he's not too surprised for being knocked out. However... "Why do you ask?"