Well, the point is that there was absolutely no way Phoenix should have the key. Whether she left the room is irrelevant because she didn't have the opportunity to change clothes or do anything of the sort before she was arrested. The police SHOULD have found the key on her person during a search, or Morgan should have had it.
The fact that they didn't meant something was up. Phoenix hazarded a guess as to what it could have meant. He wasn't correct, obviously, but the fact that he was the one who found the key meant that the case warranted further investigation, and it bought him another day.
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No objections to SuperNiceDog as our Guru champ!
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