In Saw 3D it is revealed that Dr. Lawrence Gordon, John's oncologist from the first film, is with John after Saw 1. Since this was the case, why did John kidnap Lynn Denlon (another oncologist doctor) for his operation in Saw 3?
There is seemingly no need to have Lynn Denlon because John's tumor cannot be treated as said in Saw 1 and even Lynn Denlon also said the same in the SAW 3.
Jigsaw was just testing her and her husband he didn't intend to survive that's why he recorded that little tape that he ate at the bed, also he was testing Amanda along the way.
In Saw 3D you can see Lawrence Gordon suggesting Lynn Denlon as a test subject to John along few other quick cut scenes of him setting the traps.
Why would he test Lynn since she doesn't look like bad person? Actress who played her told (source):-
"But I think, in his mind, because my character's depressed ... so she's been dead inside. She's totally dead inside and this is Jigsaw's way of waking her up and saying, 'What the hell are you doing?' And she does. You see the metamorphosis in her."
