This has probably already been talked about (I have not read this whole thread - it is really long,) but with the information that the pollen was from an Australian Pine tree, do you think there is any chance she is actually FROM Australia? November in FL is really not that warm - not warm enough to be lounging around on the beach getting a tan. But it's the end of spring in November in Australia and the average temperature is in the upper 80's Fahrenheit.
Just a thought. If she traveled here from Australia with her family or as an exchange student or something, it would be hard to make it all on your own if something bad happened. She may have even been abandoned by her family or she may have run off during a family vacation to the US.
Edited to add - I wonder if her hair is naturally curly or if it's been permed.