So we have three options for Kristoff's quotes:
The short one, the one about his job, and the one not spoken about him.
Of those three, the first and third are preferable since they actually give insight on Kristoff as an individual. Even if the first one is short, it's better than the second because in the context given, it's clear that it shows Kristoff as a selfless person who cares about his friends. Also, unless there's some clear statement that a quote must be said by the subject, I don't see why we can't use the third quote.