I would be concerned about this, as in my experience schools are asked to comment on a child’s behaviour and performance in the classroom as part of an assessment. ADHD has to be shown in different settings and not just in the home. I would be asking parents if I could see the report ( so that you can also support the recommendations). Like some of your other respondents I would chat with the parents about their view of his needs so you can try and work out why they did not involve the school in any of this. I have experienced cases where parents have reported a diagnosis based on an online assessment they have done.