We recently had a JCQ inspector look at some of our paperwork and I had, like you, been doing exactly what you have described. However, I was advised that this was essentially the wrong way around. First and foremost, they want us to have evidence of the student’s normal way of working and evidence from teachers at the school/college that the student requires an access arrangement. I had this, but not nearly enough for what they wanted to see! I was told to have more examples of tests where extra time had been used for instance. The student should have had a diagnosis based on concerns from the school and our advice to do so, and we then use that as medical evidence for the AAO. It should not not say what access arrangements are needed, only confirm the diagnosis.
I was also told that we shouldn’t be accepting private assessments as evidence, or at least we shouldn’t if there was not enough evidence of normal way of working prior to this.
So, yes, you need a detailed file note (also stating that rest breaks or other alternatives are not suitable), substantial evidence from teaching staff, and confirmation of the diagnosis to apply. This does mean that you don’t need a Form 8 or the processing scores.
I hope this helps?