So the pollen could have come from NYC. There was a lot of extrajudicial anticommunist activity there at the time.
The FBI was investigating suspected subversive safe houses in Manhattan. Montonero banker David Graiver was making his last deals in the city before disappearing in a suspicious plane crash.
And there was a massive anti-Pinochet rally at Madison Square Garden on the third anniversary of the Chilean coup. Joan Baez was apparently there. So was Orlando Letelier, the leading dissident. DINA agents were already stalking him and he would be assassinated in Washington, DC, just ten days later.
This rally was, I believe, the day before this girl's body was found! It would have been nothing for her to hop a train from Massachussetts, where the other evidence points; Grand Central Station was right next door. As I said I think was spotted at the rally and maybe snatched on the way home by some guys in a van.
She had a little guest house key and I've always wondered if the JP tattoo stood for Juventud Peronista. Maybe she was a courier for their banker in NYC.
I think it's really striking that this pollen evidence, and the timeline of events, could place her so close to all these other extraterritorial assassinations.
This was 10 September 1976, two days before this strange girl turns up dead.
Letelier's speech, for context:
https://www.tni.org/en/article/transcript-orlando-leteliers-speech-felt-forum