I've read that many times and that went right over my head. I think you've made a brilliant discovery. The size 12/14 panties were NOT found in the house. So who took them????
According to the snippet below taken from your above post:

11 Q. And I will just state a fact

12 here. I mean, there were 15 pair of panties

13 taken out of, by the police, out of

14 JonBenet's panty drawer in her bathroom. Is

15 that where she kept -

16 A. Uh-huh (affirmative).

17 Q. -- where you were describing that

18 they were just put in that drawer?

19 A. Yes.

20 Q. Okay. And every one of those was

21 either a size four or a size six.