So even if the prosecution believed she was never in her PJs, why didn't they call his bluff? It would have worked in their favour either way. Lean on him that the PJs were never found and point out what that implies - they had incriminating evidence. Either that gets emphasised along with more guilt, or he changes his story and says she might have been wearing the daggy Katie's pants after all. Neither scenario looks good for GBC, so I don't know why they didn't use it!