Hey there, Shelley! Welcome!
I would like to say your son is a wonderful hero. I am thankful he was there for you in that time!
Getting a diagnosis is sometimes the hard part...I feel you. There are so many different types of seizures. There are seizure disorders and there is epilepsy. Not all seizures will be epileptic in nature. I had what seemed most like grand mal seizures when I was 9 and I was at public school when this stuff was going on so the doctor needed to know what my teacher was witnessing at school, what my parents noticed at home, and all of that. I would basic info (name, date of birth, parent's names, favorite color, where I was, etc). It took about 6 months - 1 year to get a diagnosis. The pediatricians eventually had the impression it may be seizures, though. They had sent me to the city for an EEG. The results came back abnormal so thus the diagnosis. It wasn't until I was in my freshman year of high school...that very first week of school that I had epilepsy. So, the diagnosis was then listed on as "epilepsy".
However, I have had some issues here and there where I have gotten extreme dizzy spells lately. I was at the computer one night, it was late, and I had forgotten to take my medication. I suddenly became dizzy...hit me like a brick. It was very sudden. The room was spinning around me whether my eyes were open or closed. I got up to step away from the computer and collapsed on the floor, but pulled myself up to lean against the couch. My husband got what I needed to kick everything (low THC/high CBD marijuana buds when it's bad, full spectrum CBD oil if I feel only a little foggy) and I got better within a few minutes and about 90% better within the hour. I remember one time I was on the verge of a seizure and I had gotten home from a long road trip. I was super tired and was getting ready for bed. I started changing out of my jeans and could barely do so - I almost kept falling over and when I tried to walk across the room to get a change, my balance was nearly gone. My husband has said lately he has noticed me sometimes "tense up" real weird when I'm sleeping in bed and it just doesn't seem natural or right. So seizures for you is a possibility, but it could be other things, too - all depends on what they find or don't find.
What I recommend is:
-Get an interview from your son. Write this down in a memo pad or something for your doctor. Doctors will often ask if you have any family members/friends that witness this stuff. It's hard when your judgement is impaired to say everything about how you feel or anything like that. I try to interview my husband before each appointment these days and ask him, "Are you noticing any new symptoms?" and, "What have you noticed with seizures? What does it look like is going on (muscle twitches, fainting, convulsions, etc.)?" It helps the doctor know what's going on at home!
-Make a journal of what you notice. How do you feel before these dizzy spells happen? Did you eat anything you're allergic to before hand? What times of the day does this happen? Does this happen only at a certain time of the month? What makes your symptoms better? What makes them worse? Are you having a hard time sleeping? How long do the dizzy spells and unconsciousness last? Things like this already written in a journal for you to tell the doctor can help. If you have someone to time the dizzy spells you're having and such, that is always useful, too.
-If you have an oximeter or a blood pressure cuff at home - get your readings from time to time and write them down, too, to see if it's anything possibly related to blood flow that you might need to get a referral to a cardiologist for.
Here are a few other thoughts:
-People with POTS (Postural Orthostatic Tachycardia Syndrome) are often times dizzy because the blood doesn't flow well from the legs to the heart and dizzy spells are common with this. It's also common to feel weak, fatigued, lightheadedness, loss of consciousness, rapid heartrate increase, headaches, nausea, shortness of breath, sleeping issues, brain fog, abnormal sweating, chest pain, heart palpitations, etc. They say POTS is indeed rare, but it is also hard to pin point and diagnose. Often diagnosed with a tilt table test. Some people with POTS have said you can test this with an oximeter. You lay down on a bed, stay there 5 minutes to ensure a resting heart rate, get the oximeter ready, put it on your finger, and then stand up. If your heart rate goes above 120 and keeps on rising, POTS is a possibility.
-Many people with epilepsy also have heart problems, too. Sometimes the heart problem is the underlying cause for the epilepsy. It's not an uncommon combination. Also, the signals between your neurons messing up can cause heart palpitations and such, too. A few times when I have had epilepsy, my heart has stopped completely for about a minute or two an then it starts up again. However, I am not diagnosed with any type of heart problem.
-Sometimes people with blood sugar issues have seizure as well, generally from blood sugar falling too rapidly or too low. Although, you mentioned a lot of blood work - I assume they have probably tested for this already in their workup.
-Menstrual cycle seizures, also known as catamenial seizures/epilepsy. Some people have good outcomes with bioidentical progesterone cream at the right times of the month.