When the miniature camera is discovered in the victims eye, it is said that this would be "the splinter that turned up in the M.R.I." If the victim had had an M.R.I., the camera, having metal parts, would have been ripped from the eye by the immense magnetic field the M.R.I. produces. If a patient is unable to communicate whether he/she has any metal objects in his/her body, the doctors won't perform an M.R.I. before making absolutely sure there is none, for example by taking (several) x-rays. The camera would thus have been discovered much sooner and definitely not by M.R.I.
Harris puts cameras in the eyes of Sam and Dana, holds them captive in a non-sterile environment, and he makes the first incision into Dana's head by slamming the tool with his hand; yet they both survive and only the effects of the botched lobotomy are shown. In real life, they probably would not have survived under any of those conditions. They most likely would have died instantly when Harris slammed the tool into their heads.
When Anton reflects Dana in the car window, he says in German: "Glaubst du wirklich daß [sei] jetzt kommen werden?" which literally is: "Do you think that [they] now will come?" However he does not say the German word: "sie."