If it wasn't obvious by how panicked noah looks, this cody isn't from his 'dimension'. No, universe traveling won't be in the book, i just thought it would be a cool scenario.

Cody here is from the original total drama, before he had gotten mauled before the bear, or after he healed. I'll keep it ambiguous. Since this is canon cody, his relationship with noah probably isn't more then possibly-friends, so he's really confused at the sudden sadness from 'his friend'

Noah on the other hand, had not only watched Cody die, but he died in his own two hands. The scene hadn't been set long after the incident, so noah still feels very guilty for the death of one of his closest friends.

Along with that (↑↑↑), the ghosts of the people who had died continuously haunted him for partially being behind their deaths. So, not only is cody dead because of him, but Cody's also tormenting him everyday, and to top that sundae, noah felt guilt (see why this is an AU?).