Almost all his actions since reincarnation have been about powering up to be able to survive the main hero. And he can't recognise what the hero looks like ? I thought he was just going for a dismissive "Am I supposed to know you ?" but the following panels make it clear he's surprised…
Also, that "hero" seems super dumb and obnoxious, it'a wonder he managed to write a story that got readers (and a god) interested and invested.