If a 95 year old does not wish to wear a hearing aid, I am not sure you can compel her. You may try having her see her audiologist for a teaching session.
She can demonstrate that she can put the aid in and take it out properly, etc. She may change her mind if she sees that she can handle the device.
If she just doesn't want one and she is control of her faculties, there is not much you can do.