An ear infection shouldn't have any correlation to seizures. Seizures are, in very simple terms, an electrical storm of the brain. Neurons misfire and the result is seizing, convulsing, memory loss, etc. It works the same in humans and animals. If your dog has had three in two days, there's something going on than just an ear infection. I would definitely get a second opinion. The blood work might not show anything but a brain scan would. Not sure if they do brain scans on dogs, though.... but checking blood isn't going to give you any answers either. See if there are other testing alternatives and go from there. Unfortunately, running a battery of tests is going to be expensive. But dogs are part of the family so in the end it's worth it if it means adding to her quality of life.