Most internships have been filled now.
It's unlikely to be 'vital' in most industries (law is the exception, I'll admit I don't know much about jewellery/fashion. Is that what she wants to do as a career?)
She should try speculative application, essentially cold calling places and asking if she can come in for work experience. Google the best way to do this. If they won't offer an internship, she can also ask to spend a day or a week work shadowing to get a sense of what the industry involves.
Might be possible to volunteer somewhere? E.g. local museum, they'll probably give her grunt work like covering the front desk or helping out with kids activities over the summer but once she's there she could ask to spend some time with whoever manages costumes and fabrics, for example. Or if she wants to go into marketing, ask to spend a day with that team. Obviously she'll need to show herself willing to help them out and be useful in what they need as well! If she has a summer job, again ask if she can spend time with someone more senior whose role interests her on one of her days off.
What does she think an internship will give her?
If it's networking contacts, can she get those another way? Going to events, contacting alumni on LinkedIn to ask for advice etc. She had all of next year to build those up.
If it's too show her interest in a particular industry, is there a society she can join? Start tweeting about it. Read news articles, listen to podcasts, maybe even make her own or write a blog post/contribute an article to student newspaper on her chosen topic of interest... Something she can talk about at interview
If it's work experience she wants, recruiters also value entry level jobs,(bar work, retail, office temp, cleaning etc) if she can sell it the right way on her CV. Get her to talk to her careers service either now or in new term (they'll probably be quiet now and most do phone appointments if she can't get there in person). Leverage the experience she had as above to try and get insight into a more "graduate role"
Sounds like a last minute panic! But it's really not the end of the world. Good luck