Correspondingly, where are the ID scanner chests at the rig?
Head to The Rig in the southeast part of the map and head directly to the red phone booth that allows you to disguise yourself as one of the henchmen. Once you do that, you'll be able to head to the tower north of the small area and go up a flight of stairs to find a locked ID chest.
Furthermore, how do you open doors locked by an ID scanner? Once you're there, you can either disguise yourself as a Henchmen in the phone booth or knock one down and use him to open the door instead. Then, go toward a locked door with a scanner next to it and either allow the door to scan you or hold the carried Henchmen up against the door to unlock it.
Also to know is, how many ID scanners are at the Grotto?
18 id scanner
How do you unlock chests with ID scanner?
There are two different ways to unlock Chests locked by an ID Scanner. The first uses the exact same process as unlocking ID Scanner doors from the first week's challenges. You can find the Chests in any of the new locations, including at the bottom of the Grotto, the Shark, the Yacht, the Rig and the Agency.