Shouldn't you have got the letter and THEN booked the surgery? Sounds like your demanding a preset result. And if it takes him/her time, then you're going to pay for that time.
He/she is signing off on a professional action, and as a professional she/he needs to protect their interest in this and make sure it meets the standards required. Some of it, is CYA stuff to be sure, but a good professional always does CYA or they are not professionals for long.