The one point that contradicts any use of drugs or alcohol is that she made a phone call at 5:50PM, and there's nothing special about that call. It gives no information regarding her disappearance nor her state of mind. The video gives me the impression that she is stumbling around, but maybe she's just not that coordinated and a bit of a chaotic stumbler when using the phone.
At this point in the video, she steps with her left foot across the right, then turns and leans to the right - it doesn't look normal. This is not a jittery video (as some suggested), but unusual walking.
Regarding drugs, they don't hit people all at once. It is a gradual process where, if she is involuntarily under the influence, her first thoughts will be "what's wrong with me," followed by the decent into
being completely out of it. Could she be under the influence, but not fully under the influence?
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