Not a lawyer, but reading your posts it seems as much about your DD being worried about next steps after a set back.
The answer may then lie in why she had problems first time round.
My DD really struggled in her first year at University, which came as a surprise not least because she had moved for sixth form and settled instantly and then had no problems when working overseas during her gap year. Looking back it was pure and simple bullying. The alpha female in her flat of twelve effectively acted as if she was in Yr7. It took most of the following year, sharing with lovely people, and a nice group of friends, for DD to regain her confidence. Your daughter's problems may have had a different root but from what you say she was not struggling academically.
Whatever she chooses, and your posts suggest she is inclined towards giving University another shot, she has a few months to build some resilience and skills in friendship building.
What kept DD going was having made friends through sport, and another good friend on her course. There is an assumption that you go to University and live in halls in order to make friends, but it does not always work out that way and having friends from other contexts is a big help. It can also be difficult for young people who have had a strong friendship group at school to branch out and make new friends, especially if it involves making the first move.
What interests her? What might she like to carry on with whilst working or at University? Drama, sport, volunteering. She can join clubs/groups in London or at weekends. (I still think.she should explore private halls for her first year. And ask the college that she will be attending about any social life they help facilitate - it must be a common problem. Plus they offer undergraduate degrees.)
If she started now joining or getting involved in a couple of things locally, it should help build her confidence and get her used to being outside her comfort zone. And ready to engage wherever she ends up.
It wont help with the choice, but will help with her thriving next year.
Two fantastic opportunities, which is a good start. She needs to weigh up pros and cons carefully and then go with her heart.