Welcome back to the site, Charlie. I'm sorry to hear what you are going through, as I realize what an important decision it is. I have always felt that far too many students find themselves in the position that you are in and I wish there was a way these situations could be remedied more easily.
You are indeed lucky to have options, but I can obviously understand why you wish to go to the NYC school if it is your dream.
If your parents will not
co-sign or ask someone else to
co-sign on a loan, do you know anyone you could ask on your own who may be willing to do so?
It definitely sounds as if you are putting forth a lot of thought and work into this. You mentioned being offered scholarships from both schools and I hope that between that and your other efforts that you can work this out. The above poster's suggestion of speaking with a counselor to possibly help you sort this out is a good one as well. Best wishes.