Immigration Issues/Form DS117
My had green card but she overstayed in India because of health issue and she couldn't travel. As we hadn't planned this I hadn't applied for re-entry permit. Now she wants to come. So planning to apply DS-117 applcation to regain resident status.
Next question. When she got her green card she had a tourist visa 10 years multiple entry which still hasn't expired. In case she won't get her resident status back . Can she use same tourist visa to travel to US or need a new tourist visa.
I think your mother would be able to use the tourist visa to visit the United States if her permanent resident status cannot be reinstated.
I would recommend filing for abandonment in the Embassy for the green card first, before re-entering the US on the tourist visa to avoid any problem with immigrant intent.
She also needs to prove to the Custom officer that she will return home after her visit. It is not a guarantee that she will be admitted, but most likely she will be if she has a clear plan for what she wants to do in the US and when she is leaving.
Be sure to get her a round-trip ticket.