Lougle I am sat here going through ds's SALT reports and trying to see if there is anything that could help you to get your ds's needs identified.
Has a SALT ever observed your ds in the classroom? when I say observed I don't mean for 5 minutes.
I will say that when ds was observed it really showed his functional ability.
He was observed during a literacy lesson (storyboard). All other children joined in the discussion and raised their hands contributing ideas, ds didn't.
When back at the tables, ds spoke a great deal, but did not engage with the task until the TA came over and asked him directly who his character would be he replied 'sponge bob', he was encouraged to use his imagination and think of another. Took a great deal of prompting, before replying 'castle' (naming the picture the girl next to him had started to draw, to add her character to)
After lots more prompting by TA to think of characters associated with a castle, he named 'princess' (again copying what the girl sat next to him had added to her castle by this time)
TA then asked him to name another he replied 'king guard'. TA asked did he mean king or a knight. He looked puzzled by the word 'knight' (thinking night) and replied 'guard'. The TA stayed with him, to talk through what to do next and what to write.
He then drew a picture which he named 'king guard' and wrote underneath 'he has good smarts'. At the end of the lesson, that is all the work that ds had done.
TA then shook a tambourine for children to stop and put hands on heads to show they were listening, ds did not attend.
Yet he had been discharged by school SALT after scoring above average in all formal assessment (90th centile, 84th, 75th etc) about a month before. School reported 'no difficulties' and he was doing totally fine!
Just because others might not see what you see, doesn't mean you've got it wrong.