Refused Housing Benefit and not received a migration notice

Hello,
My Brother has a profound learning disability. I am his sister, appointee and advocate. He was forced to move to supported living accommodation from his residential home by social services with no transition period. I was advised by Citizen's Advice to apply for Housing Benefits. I have done and this was rejected due to the landlord being LTD company who makes a profit and does not meet the criteria any longer for Housing Benefit. They advised me to apply for Universal Credit. I have appealed this decision.

Universal Credit said I should not apply for UC until my brother receives a migration notice. They advised me to contact ESA who issue migration notices which include transitional protection. I spoke with multiple agents, wrote letters and currently going through the DWP complaints process to try and get them to issue a migration notice or transitional protection.

I was wondering if anyone has had any success with a similar situation or any advice. I have had numerous conversations with Citizens Advice (both local and national) and Disability Law Service, who advised the complaints process and legal action. I am also writing to my MP.

The move was forced by the local authority, this was not my brother's choice and so I can't believe that there is nothing in place to protect his benefits and ensure that his housing payments are paid.

I am currently waiting on a response regarding the appeal as well as response to my request for an early migration. Rent has been due since October 2024.

Any help would be much appreciated.
Many thanks for your time and energy reading this.
K