Ok...I don't know if this has been discussed before. Just some thoughts and they aren't related...Just random thoughts...
Any chance Sam went into a witness protection program? Not sure how that would work. How do people go into those? Don't they just disappear?
Any chance the delay from person A reporting the card was due to the fact his vehicle was not robbed, but because he maybe was robbed by someone from an adult ad on craigslist or something that was not above board? I am not trying to say Sam placed ads, but, if she was the one who took this card after "visiting" and IK ends up with it, then maybe that is a link.
Or, any chance perhaps Sam got pregnant, wanted to hide it and went to have an abortion or take the abortive pill and she did not survive it?