Stonewalling from the NHS over records is not unknown.
Scenario: after investigation by the NHS, we got a diagnosis as to what was wrong with the child. The only treatment offers from the NHS were horrendous, so it was time to dust off the private insurance.
So we asked the NHS to send all the results of the tests, scans, etc, to the private doctor. "Nope, the NHS did that work, if you want go private you go private the whole hog, and pay for all the tests to be done again privately."
So after a bit of research we did the access to medical records bit, and they gave the stuff to us, and we passed it to the private consultant. Weird that they completely refused to send it direct, and didn't offer to give it to us instead until we came back later and used the right magic legal words.