The only other thing I can think of is to contact your mom's carrier and see if they have a backup of her contacts. Most carriers do offer this service, but I think you generally have to sign up for it, so it may not help you out. Still, it's worth a try.
Just make sure the customer service rep knows what you are talking about. Verizon calls it "My Verizon," both AT&T and T-Mo call it "Mobile Backup," and Sprint calls it either "Sprint Mobile Sync" or "Wireless Backup." Good luck, I hope you are successful!