Just because a character's internal narration isn't shown doesn't mean he is a totally different character. Instead, it just means you don't see his thoughts. I guess you can make up reasons for his behavior that aren't true to his character and act like they're true, but it seems like the only reason to do that is to annoy people who know the real character. Nobody cares if people speculate about his character, but to say he's a selfish, heartless bastard because he did X and not considering other reasons why he did X is just pointless.