Thanks for the replies so far all.
We are going to hit it hard with RM, See and get a police crime reference.
If all else fails, do people think turning up (with all our confirmation emails, Id's and other proofs like bank statements printed off) is unlikely to work? I'd have thought we can go to the box office with all that and they'd take a view that we are legit ticket holders?
This is our first glasto and we were so looking forward to it, such a ridiculous situation 😞