First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes.
From the description you provided it sounds like you are describing herpes encephalitis. Many people have chronic oral/facial herpes (HSV-1) or genital herpes (HSV-2) that usually exist in a resting state in the body. For unknown resons they cause cold sores, genital lesions and sometimes and infection of the brain called encephalitis (this is rare 1 in a million compared to all the people with chronic HSV-1/HSV-2 infections). When herpes infections the brain it affects the frontal (behind the forehead) and temporal lobes (behind the ears) the most. It causes a hemorrhagic necrosis (it bleeds and dies) which leads to seizures, memory loss, problems speaking and often cognitive problems (dementia). If this infection is untreated it is usually fatal (death) in 7-14 days. With aggressive treatment with IV acyclovir early, the outcome is still guarded with many complications despite all efforts in many cases. These patients will require longterm care, for seizures, memory problems and behavioral issues. many are able to walk/talk, but are unable to care for themselves due to their injuries. Some fortunate patients are able to survive with mimimal cognitive damage and their seizures are able to be controlled with medications. I would suggest a repeat MRI of the brain to assess the damage that has occured due to the herpes infection and an EEG (electroencephalogram or 'brain wave test') to evaluate for ongoing seizure activity. If your friend is from Alabama, the best place close to you would be UAB (University of Alabama-Birmingham).
I hope this has been helpful.
Seizures and speech loss may be from a different disease, brain tumor usually causes this, please advice him to visit a nerologist