Sorry to read about the problems you and your daughter have had with your hospitals.
From what I understand, due to the mistakes made when you daughter "became an adult" the pump management was not transferred. Now she needs some new pump supplies and there is no account to provide this.
I assume you have spoken to DexCom and explained the situation?
I had an issue with them when they said they did not have details of previous orders but when I pushed them they found these details.
I would contact Trafford where she has her upcoming pump appointment and demand they take responsibility now. An appointment should not be needed to continue her current treatment.