So I have confirmed the nefarious purpose of the ATSHA204A. When you switch sensors between camera boards they continue to function. But when you remove the ATSHA204A the board stops working. Which means it is meant to make sure the Pi Camera Drivers will not work with cloned boards unless they have a ATSHA204A with the correct secrets programmed in! As if it wasn't bad enough we had to deal with a close sourced blob for the video core!
I have a PiCamera I thought the sensor was broken on, but it turns out the ATSHA204A was borked, the sensor works on another board and now there is no way for me to use that sensor because I don't have a matching crypto chip for the driver!!!
I have also confirmed my schematic and PCB layout are good, transferred over all the components to my OSH Park boards and the sensors function.