difficulty with school support on higher functioning side of and

Ive had a meeting with my son's school today, regarding supporting us with an asperger's assessment through the ISCAN PANEL. We've been told in a nutshell, that yes my son has some behavioural difficulties, however they are few and far between and really theres not very much the school can do to support. 

Now, he has been on an IEP (individualised education plan) for the past 2-3 years, with comments such as 'things i find difficult are: changes to routine, managing my anxiety, having awareness of others in the class and controlling my emotions'. I also have past comments from his school reports, such as : 'he likes his own company, he likes to help adults and peers when it doesn't conflict with his interests, he has very fixed views and opinions, he can get upset about somethings when he is wrong, he has rigid organisational skills, he has a sensitive nature'.

My argument is, this is the evidence to suggest he has asperger's, alongside all of the subjective evidence i have at home on his behaviours. 

My question is, is this enough evidence to ask for and assessment?

Anybody with experience of this, please share, as i feel as a loose end. What other evidence can i collect?

Thank you.