We need your help! We know there is a cache somewhere in the area of the coordinates above, but we're unable to find the final location. Agent Chiffrage believed that the final location was contained in this intercepted message "DMKZPBPHETGEAMKOPOAHETGBN", but he went missing before solving the puzzle.
The only clue we recovered was a scrap from his notebook with the following text:
"Je pense nous sommes sur la voie droite. Je crois que la clef est secret et il a 6 caractères. Si nous pouvons seulement casser le chiffrage, nous connaîtrons l'endroit de leur poteau à distance d'écoute. "
Your mission is to use Agent Chiffrage's notes to break the intercepted ciphertext, extract the coordinates, and find the cache.
Thanks to Team Slytherin for the inspiration for this cache, and for providing the cache box!
You can check your answers for this puzzle on Geochecker.com.