Can Social Care be compelled to attend Annual Review meeting?

Our daughter (aged 22) is currently at residential/supported living further education college in Hertforshire. She needs to leave this year and so the LA requested an early Annual Review meeting which takes place this Friday. Whilst the SEN Caseworker will be in attendance, the social worker who was assigned to our daughter's case last year has been taken off her case and as yet, nobody has been appointed by the Social Care team. Are they legally bound by SEN guidelines/COP etc. to attend?

It is fundamentally important to have them part of the process, as we have to decide where our daughter is going to live. We are currently looking for residential care home closer to our home (in Farnborough, Hampshire). So they need to be integral to the whole transition process.

Any advice would be welcome. Thanks.