From the described symptoms i would consider the possibility of seizures to be high despite the normal EEG and the Neuroimaging
. The body soreness and difficulty to walk following these episodes further strengthens the suspicion of Seizures. Kindly take a second opinion
from another Neurologist
The possibility of Non Epileptic event cannot be brushed aside but an organic cause definitely needs to be excluded before such diagnosis is considered.
If possible make a video of the fainting
episode to be shown to the Neurologist during your next visit as it will convey much more information than a verbal description. Also pay attention to details like if the eyes are held open or closed, are there any abnormal movements of limbs
or body, thrashing or thrusting type of movements, deep fast breathing, color of face and lips(draining of color or pale ) ,response to call,tone of the limbs(stiff or lax) etc.
All these detalils will help your doctor in making a correct diagnosis even when the investigations dont help !
Hope this helps! Kindly get back if you need further assistance!