Is it normal to have a dark skin pigment in the vaginal area for older women with no symptoms of something wrong.

Yes: age related atrophic /menopuasal symtoms can cause vaginal color changes

Probably: If it is a focalized dark spot then it may be something. If the whole area is hyper pigmented it is fairly common and not a problem. Good health

Hyperpimentation: Could be normal especially in areas that have had prior skin issues in the past. if no symptoms and no eruptions may be observed