Is the neuropsych exam still upcoming?
You make astute observations and you are thinking carefully about your son's needs and difficulties. I would, however, suggest that instead of playing the game of "is this behavior a symptom of X?" leave it for now to the neuropsych. List and organize all the behaviors and issues that you observe, and present them during the evaluation.
It is sometimes very difficult to tease apart the issues into different diagnoses. The game of "is this ADHD or ASD of EF or fine motor?" is fraught with subtlety and ambiguity.
That being said, I've never experienced an evaluation for either kid that was totally satisfying, sometimes with obvious gaping holes: We took DS to the local university hospital in which a team of 5 faculty evaluators did a comprehensive evaluation. This should be the regional gold standard. The school looked at me with wide eyes amazed I'd gotten him in. It missed the boat big time. It was frustrating a demeaning. But it did get us one accurate diagnosis, which helped us progress on the most difficult issue, but because I'd spent so much time trying to piece together the kid myself, I was very resistant to a few of the other diagnoses. Once we'd progressed on that issue, then a subsequent evaluation (this time by the school, but with a hand picked evaluation team) got us something that seemed much closer to explaining the kid and helping us plan a path forward.
This is a long way around to saying that if you feel you can accurately describe the difficulties, do so, and organize the information in a manner that's easier for the neuropsych (or developmental ped) to consume. Assume that the results of an evaluation will be dissatisfying for a complex kid, take the results that seem most pertinent to your struggles, follow up with evidence based treatment, and proceed. A subsequent evaluation very well may be needed once you've made progress and you have treatment data.
That being said, I know it's hard not to know what's going on and to not have answers. It's natural to seek out answers for yourself when forced to wait. Meanwhile, vent, ask for suggestions here, and enjoy that field trip.
