A friend of mine here at U of T only got about 40 hours of shadowing and received an interview from NYU a couple weeks ago. We have nearly identical stats. She applied back in July though. I imagine it just takes longer for NYU to review international applications.
I did call my top choice schools (Penn, NYU and BU) and they all said that my apps were complete and that there was nothing they could see holding it up. Everything was received and in order. They even told me that my outstanding prereqs (currently taking a half year of English and Physics each) wouldn't hold up an interview invite.
The only solace I found was that NYU told me that they hadn't even booked any November interviews yet; they only book interviews for a few weeks notice. And BU only starts interviews in October anyways. So I suppose at the very least, should I receive an interview sometime this week, it's perhaps likely I'd interview before December.
So I suppose I'm just unlucky, haha. Here's hoping I hear something soon... 😳