This happened to me many, many years ago.
I did get in to a university through clearing ; a university that I hadn't even considered when I was riding high. It was hard and I felt humiliated.
It would have been better if I had been expected to do badly. As it was, I had to endure days of, "I can't believe this has happened to you" comments.
October rolled around. I went to the 100th choice university, with a chip on my shoulder. No-body asked me about my A level grades-it was all ancient history and before long, I settled down, had a happy time and did very well.
Since then, I have had a successful career as a journalist and I have never been asked for my A Level grades.
Your daughter's disappointment and shock will fade but, in the meantime, I send you good wishes.