Undiagnosed "epilepsy" in infant, uncontrolled by medication

my son is 4 months old. He was born with a blood clot which caused a stroke and he stroke resulted and seizures we noticed four hours after birth. he was discharged from the NICU 9 days later on the anti seizure medication keppra. At 2 months old his neurologist decided to wean him off the keppra and see if he had outgrown the seizures. After a five week weaning process he was medication free for 1 day before he had a seizure. so they put him back on the keppra at a lower dose and 3 weeks later he had another seizure. his stroke was left sided which affected the right side of his brain and the seizures he had in the hospital were right sided, but the two that he had at home were left sided. so his neurologist decided that in addition to the keppra he was going to start him on trileptal. after being on trileptal for four days he had a 45 minute seizure and was taken by ambulance to the emergency room. He had 4 more seizures in the week that followed all lasting 15 minutes or more. he was admitted to the hospital where they ran an MRI and an EEG. None of which showed anything different than the ones he had as a newborn. beeg just confirmed that he was having 10-20 second seizures while he was sleeping. They took him off the trail up doll since one of the side effects can be more increased or severe seizures and his body was not handling it. Instead they put him on Vimpat (Lafosamide) in addition to the keppra. He has been on it for one day and is now having what we thought were absent seizures where instead of his body shaking like they did with the long seizures he just stares into space and does a repetitive chewing motion. However he had three in the span of an hour or the shortest being 4 minutes and the longest being 14 minutes. So they are not absent seizures.  so basically where we are at is that his seizures jump sides, sometimes they are partial sometimes they are generalized sometimes they are left sided sometimes they are right sided, he has them while he is sleeping, and now he is having staring spells that last way too long. Medications dont seem to be controlling them but instead changing their form....These increasingly long seizires in the long term can be very damaging to his brain not too mention the strain it puts on his tiny body. We are completely heartbroken right now with no answers. I am telling our story in the hopes that maybe there is somebody out there who has had a similar situation and can offer some insight as to what might be going on with our poor baby.