Having looked at IPSEA I think that they are covered, sadly. It says:
"Under point SEN Reg 6(1)(h), a parent or young person can ask the LA to seek advice from anyone within education, health or social care, as long as it is a reasonable request. This can include a speech and language therapist, occupational therapist, physiotherapist or someone from CAMHS (Child and Adolescent Mental Health Services).
A request would be considered reasonable where, for example, a child or young person has been identified as needing an assessment already and they are on a waiting list, or where the school, college or other professionals have said this advice may be needed."
The SEN department say they will only ask people already involved and if I want them involved I have to seek that:
The SALT department has rejected the referral because they say that her difficulties are a function of her ASD.
The OT department say they don't do sensory so won't accept a referral.
The Specialist Teaching and Advisory Service Communication and Interaction team, on the phone, said they only deal with people who have an EHCP already. However, I had emailed the service lead prior to this and she has replied to say that she will try to help DD2 and asked for the case co-ordinator's email address, so that's something.