Claude Levitte the perfumer has been doing well as an informer—he talks to the Germans, and is rewarded with food and money. When von Rumpel arrives in Saint-Malo, looking for Daniel LeBlanc, he talks to Claude. Claude points von Rumpel to Etienne’s house.
Predictably, Claude Levitte is the one to tip off the Germans about Etienne’s house. The end of Doerr’s novel is filled with satisfying confirmations of this kind, as more plotlines have their loose ends neatly tied up.