Jeff there are organizations that will help with vet bills for a pet and I believe also help with the cost of medication. They are called
The Farley Foundation and may help your Mom. Please click the name to go to their website.
I also wonder if the vet is worried that your Mom's dog has a rapidly advancing problem causing the seizures because they have only been happening for 2 weeks and have progressed to 2 a day. The vet may be preparing you and your Mom to lose her little companion
BTW welcome to Pets.ca