I've also taken Keppra to maintain my seizure activity successfully for over ten years and am still wary of it's side effects. One very important thing your article mentioned was recognizing a trigger, it can help immeasurably to understand how and why your seizures occur. Definitely discuss your suspicions about these specific causes of your seizures and why/when they are occurring with your doctor.
Is it ONLY when you take vitamins/supplements that your mini (possibly focal) seizures occur? It's an interesting trigger for seizure activity. Try to discuss what supplements are causing you seizures, their onset and how often they're occurring; much like in your article. Sometimes writing that information down prior to an appointment helps ease the conversation and end up providing you with a more specified response. There may be a common ingredient within the supplements you've taken that you respond to, or it could be a variety of other reasons.
I'm sure this seems like mundane advice but when it comes to any form of consistent seizure activity, it can be individualized and different for every person, so talk with your physician.