Arrested along with Benjamin Cremieux April 23, 1943 by the Gestapo in Marseille at the tavern Charley, 20 Boulevard Garibaldi, Multon talked without any physical coercion against him and accepted the proposal of Ernst Dunker, aka Delage, to work with the German authorities.
First, thanks to a resistance fighter at Marseille, Charles Le Couster, arrested May 15, he was aware of the mailbox that Suzanne Dumoulin kept at 10 rue Bouteille had put at the service of the Résistance-Fer of the MUR.
Then, because he had the means to contact Henri Frenay through the mailbox of the Hotel de Bourgogne in Mâcon, which information was provided by Berty Albrecht whom he had met at a meeting held in Marseille in early April 1943 at the home of Chevance-Bertin.
The message, written in clear text, was intended for René Hardy, alias Didot, to prevent a meeting on June 9 at 9 am with General Delestraint at the entrance of the metro station La Muette in Paris.
On the other hand, Aubry forgot to prevent Delestraint and Hardy when he found out that the mailbox was compromised since the liaisons Combat broadcast information from the arrest of Mary Reynoard.
On the evening of June 7, Multon and Moog took the train to Lyon Perrache to return to Paris where a trap was organized by Eugen Kramer, head of the Abwehr, at l'hôtel Lutetia, to seize the General Delestraint.
Meanwhile, Multon and Moog, who continued their journey to Paris, June 9 participate in the arrest of General Delestraint who also trained cells from Joseph Gastaldo and Jean-Louis Theobald.