I used to care for adults with multiple disabilities, most of whom were in receipt of the old mobility benefit. There was one chap who, unusually, could run, and at a good pace too. Thing was, he had no idea where he was running to - like into a busy road - so he had to have his hand held at all times when out in the street. Yet because he could run, he was classed as not eligible for the benefit.
When my mother first applied for DLA, she underplayed her disability, not wanting to seem any less capable than she was. She was subsequently turned down. So she applied again and, on the advice of my social worker boss, milked every ounce out of her disability when it came to the medical assessment. She got the benefit.
It's not something that honest, hard-working people like to do, but it seems to be the only way you'll get any of them to take you seriously.
Unfortunately, Tweeny, I'm way out of date on disability benefits, but I hope you and TUT both get the results you want.