Sorry to hear you lost all that hair, but wow: there are SO many things you did right in this situation:
1. You told the stylist specifically
how much hair you wanted to part with.
2. You went to management to advocate for yourself when you were dissatisfied (so very, very few people actually dare do that).
3. You looked beyond your personal upset about your cut and showed a lot of caring toward the people your donation might help.
4. You made a very reasonable, cautious choice to refuse further services from a salon that already gave you an unsatisfactory service.
You deserve a GOLD STAR
As for asking for products, I have this idea that we get to ask for whatever we want, with the understanding that someone has the right to refuse the request. I think it's perfectly fine for you to ask for product. It's a creative and reasonable request too IMO. Just a little gentle advice going forward: You may want to forego any more free cuts. Your odds of getting a good cut will go way up if you research stylists who specialize in cutting and styling curly hair, and have a lot of positive online reviews. Meanwhile, thank goodness hair grows back, right?