my 12 year old son has been declined for a re assessment for aspergers!

hi all really need someone to talk to or advice i don't know what to do next my 12 year old son has been under the cahms services since the age of 6/7 the school nurse refferred him when myself and his class teacher raised concerns about him,they then refferred him to the boathouse to be assessed for aspergers by the age of 10 but they said after there assessments that although he shows some signs of difficulties that can be seen in people with aspergers there wasn't enough for a diagnosis,mainly because he scored average in some things such as they said he can show some emphathy and also facial expressions in the assessments they came to the conclusion that he just has anxiety and this is made worse by him having sleep problems so they refferred him back to cahms service to have more concilling with some of his anxieties and to a peadriction who prescribed him meletonin to help him sleep,what drives me mad is that they think everyone with aspergers are automatically going to act exactually the same,whether you are on the spectrum or not you are still an individual person,i didn't agree with there decision and nor did a few of his teachers at primary school he was attending at the time including the senco teacher who even went for a meeting with me at the boathouse to ask that he is re assessed which they did but still they said the same thing.I have recently asked cahms if he can be referred back to the boathouse because i still believe that he has aspergers and so do other family members,he has a older cousin who is diagnosed with aspergers so we know the signs of it,he has been going to cahms still since he was last assessed and has overcome some of his anxieties mainly quite a bad phobia he had of dolls and mannequins,but still i see the same signs in him,one of his biggest difficulties is school,at primary school they were very supportive and helped him alot but now he is at high school he isn't getting so much support in year 7 he was in the foundation(senco) class and he was still having some struggles but was coping better with the work and going to classes but then they decided near the end of year 7 to put him into the mainstream classes and he is really struggling he is getting detentions and put on report constantly and he was even excluded for a day last week,the main reasons he is getting detentions is because he hates the lessons that much he is trying to go to one of the support teachers for help which is resulting in him being late or even refusing to go to the lesson completely,he is also getting detentions because his teachers say he isn't trying to do his work but he says he is trying but when the teacher explains what they have to do he does understand what he has to do most of the time but struggles to put it from head to paper if that makes sense,he just starts to feel really wound up like he needs to get out of the classroom,plus it doesn't help as in these class unlike the foundation class he was in it is more noisy which doesn't help when he is struggling to concentrate,i have had meeting with his head of year but they said they won't put him back in the foundation class as he is to clever for the work in there,they basically said the only way he could get more one to one support is if he had a statement saying he needs it as it is all down to funding,but i have now had a letter yesterday saying the request of re referral at the boathouse has been denied as he has already been assessed,what do i do now??,any advice would be appreciated i just do not know where to go from here but i know i cannot give up until i get him the diagnosis and the help he needs,because until i do he is suffering and struggling ,wondering if there is anyone else in the same/simuilar situation