Evidence gathering appointments

Hello, my husband is a vet and filed for disability in September 2024. He had three appointments set up back to back for his psych, hearing, and general (back pain, neck pain etc) in January. He also filed for TBI and when he went to the GP they were talking about it but the GP said unfortunately that wasn’t listed on his paperwork but that he is who he should see for it. So he called the VA and asked why it wasn’t listed and they said they were looking for a different provider for him to see for that. It’s been over a month and they are still “looking” why wouldn’t he just see the person he already saw? Especially if that doctor is used to dealing with TBI diagnosis? Just curious if anyone can give some insight

Thanks in advance!