Insurance help

Hi, I need some guidance. I'm applying for accounting and finance, and my 3 options are Uni of Manchester, Uni of Nottingham, and Cardiff Uni. I plan to firm Manchester, and for my insurance, I am unsure of whether to do Nottingham or Cardiff. I received a D in a level maths and am retaking, and all these offers require me a B (contextual offer), which. Cardiff is more lenient, so if I get a C, then they may accept me, but with the recent stuff going on, idk if it'll be a good uni to graduate from. Plus, Nottingham is more prestigious and more business connections.
Another option is that I firm Manchester and insure Nottingham and if I don't get into either I can apply through clearing with Aston as that has a good placement year option I heard and has all the accredited boards. Idk why I didn't do aston despite it being closer instead of Cardiff, but I am heavily regretting it now. So I need advice. What do I do? I really want to go to Manchester or Nottingham, but idk if that'll be a wise decision. Also, I contacted UCAS, and it's too late to change my option. I've spoken to Aston, and they said accounting and finance will likely be up for clearing as it has been for the past 3 years, so yeah. Can any1 provide any guidance?