How do we go about finding an EP that would be acceptable to the local authority?

Hi.
I am contacting you about my 9 year old son who has ASD, learning difficulties and severe allergies. At his statement review last year we were advised by school that we should move him into Special school as it is clear he will not be able to cope in mainstream school beyond the end of year 4. The SENCO who told us this left shortly after the review meeting and a new SENCO started in September.

Initially we contacted the school that was suggested at the statement review but were advised that our son does not have severe learning disabilities so does not fit their criteria. That school recommended three schools for moderate learning needs which are out of Borough. One is only 3 miles away, the others 15 and 20 miles away.

We looked at the nearest one to us, and liked it. Our son knows other children there as well as some of the staff. One member of staff works between my son's current school and the moderate needs school including working with my son. We talked to her and to teachers at my son's current school who know both the moderate needs school and our son. Without exception all said this school was perfect for him in every way.

An EP new to the area assessed him so a new report could be included in the application. The EP report was poor, not at all thorough so I was quite worried about it. The new SENCO was reassuring and said it would suffice. My son's teaching assistant was present with my son the entire time of the EP visit. She told me that she was surprised that this new EP did not even speak to my son while he was assessing him. Totally different to the EP who has assessed him in the past.

Apparently new EP advised the Panel that my son is on the 70% percentile for language. This is wildly inaccurate to say the least. My son's class teacher (who was also his teacher in reception and part time in other school years) advised it is impossible for him to be assessed as so high achieving. My son operates on a level so far below his peers as to have a differentiated curriculum in place.

My son's maximum attainment at the end of year four, achieved with one-to-one support, was 2c for reading. I'm not sure what percentile this puts him on for reading, but it is certainly not the 70th! He is on the 1st percentile in at least two areas.

The out of Borough Council rejected the application for a place at the special school on the grounds that our son's attainment levels, particularly the 70th percentile for language, are too high for a moderate needs school.

I know for a fact that the school we are looking at does have places. The head teacher said if need be they could "make" a place for our son because he believes our son is ideally suited to them. His wife works with our son so he has "inside knowledge" about our son.

How do we get a proper, thorough report/assessment, which involves the EP actually interacting with our son rather than just observing? We can afford to pay for a private report if need be - but how do we go about finding an EP that would be acceptable to the local authority?

I shall be very grateful if you can offer any advice.