Unconscious After Seizure

Hi everybody. My brother had a seizure a few days ago. While standing, he suddenly collapsed, his muscles were stiff and his legs were shaking. He was unconscious during the whole event off course. But he remained unconscious even after the seizure for about 10 minutes. He was then injected sugar serum and then opened his eyes. He didn't feel confused or anything, rather he was shocked. He vomited many times and was very sweaty, his eyes were bloodshot red. After 30 minutes he became normal. My question to those suffering from tonic clonic seizure: has anybody experienced being unconscious after the seizure for 10-15 minutes? I don't mean a typical sleepiness or weakness that often happens in post-ictal state, but rather being fully unconscious and motionless, just as if you're in coma or very deep sleep. I have done a lot of research on epileptic seizures, and have watched a lot of videos of people going through different types of seizure. Never seen anybody being unconscious after a seizure, people often come back very confused and weak once the stiffing/jerking is finished. I am trying to understand if my brother's seizure was PNES, epileptic, or syncope. He did EEG, MRI, and heart examination. Everything was normal. This is quite odd... Similar thing happened to him 2 years ago, he collapsed and remained unconscious for 10-15 minutes followed by vomiting. His eyes was closed during the whole event. No rolled back eyes or twitching. Also, he said before the drop, he suddenly felt very dizzy and as soon as he wanted to ask for help, he fainted. I really appreciate any feedback.