I am completely failing to see how Wannacry could have affected the operations of those devices AND at the same time leave some data "good enough" to produce th

I am completely failing to see how Wannacry could have affected the operations of those devices AND at the same time leave some data "good enough" to produce the fines. I presume that essentally it is a photo taking device that superimposes a date/time and detected speed (and maybe also OCR's the license plate). More or less three or four pieces of data: 1) picture 2) date/time 3) speed 4) (maybe) OCR'ed liense plate number If any of these items were encrypted it would be evident, and the following step (looking in a database for the ownere of the license plate number) would have returned a null result. The only way for this to actually work (creating a wrong fine) would be if ONLY the license plate number was encrypted by Wannacry AND the encrypted string matched another existing license plate number.