The daughter of blues legend B.B. King is WRONG ... her dad is not being grossly mistreated by his manager -- this according to King's own doctor who says he's not being mistreated at all.

B.B.'s daughter claimed his manager, Laverne Toney, was ignoring clear signs of medical distress and insinuated money was the end game.

But we just got a statement from a lawyer hired by Toney, who claims to rep B.B. King. The lawyer included a statement from B.B.'s doctor of 10 years, Dr. Darin Brimhall, who says, "The care and treatment that Mr. King has received, and continues to receive, is medically appropriate and I have seen no signs of any mistreatment of Mr. King."

What the lawyer DOESN'T say is interesting. B.B.'s daughter says her dad is at death's door, and the doctor doesn't dispute that.