Ah, "Agent Charlotte". I'm sorry to hear of your let down especially after your travel time invested.
Ive never used Bond Girls or indeed any agency other than my usual tried and (mostly) trusted for many years now. I won't reference them again. I will say that, in getting to know the owners of the agency over the years they have told me in the past that they do have the most problems with the very young girls. They join the agency, make all the right noises to the owners, have their pictures taken and maybe turn out a couple of times for trusted regulars to vet as the agency tries to get a feel of the girl. She can win points in these early days so that the agency trusts and recommends her and maybe takes a booking, like you had, only for the girl to let them down or not turn in for work, especially if she maybe had a payout the night before and has cash in her hand and decides to go partying instead.
They don't last long with this attitude but they are the cause of frustration to decent agencies. I'm always warned about this potential let down with all but the most proven of the very younger girls.
Having said that, for Bond Girls just to shrug their shoulders and say she's not available is not good. She may well have let THEM down on your booking but it's for them to do their damnedest to at least offer you an alternative girl and an apology.
Any agency or service provider is reliant on their team and any company in any industry can fuck up. It's what the company does about it or tries to do about it if it happens that is the telling point in my book.
I agree with the rest of the chaps, though. A negative review for this matter is fair and reasonable.