I'd let her go, on balance...
I can understand your concerns especially if you feel the school has a cavalier attitude, so you need to contact the centre direct and talk over your worries.
Here in the UK, do you ever take your dd on day trips to places that offer things like mountain biking courses, go carts, older children's adventure playgrounds with large rope swings, etc?
There are lots of places - children's farms for instance - that offer some attractions for active, older children. Could you go to a local one your dd can have a go and you can help her?
My oldest son went on a similar trip in year 6 and loved it, as did all the boys and girls in his class. I do know that some other parents had reservations, so I realise it's quite common.
I think one really important thing to stress to your dd is that she must listen to instructions and follow them immediately. This is so important for her safety. Is she good at this?