Not appearing a riddle the Riddler: \"Mercenary happy....\" (Batman: Arkham Knight)

Heartfelt greetings to all!

I pass the quest the revenge of the Riddler all those who have passed, all the trophies collected, all the shields are destroyed, it remains the LAST mystery of the Riddler, by process of elimination figured out it: Mercenary happy, perfect price. Hit without a miss — get off.

BUT! There are two problems:
1) Enigma not set in the menu, which shows all trophies, shields and riddles at the scene of the riddles written whole family - your time
2) the Internet has already found a hint, you need to take a picture of a picture on the white Board in the conference room at the police station, but on the basis of paragraph 1, the puzzle is not given and no photos.

Currently on the main storyline I have the mission where you need to surrender to the Scarecrow, to save Robin.

Asking for help and advice, thank you in advance!

PS. play on the console , I don't think this is a bug