[BoomerSooner]

Couple of points on the medical aspects:
1. A doctor's decision to restrict someone from driving is almost always made in the interest of public safety. Losing consciousness while operating a 2-ton hunk of metal presents a danger to the public. Losing consciousness on a football field probably creates a danger only to the person losing consciousness. Furthermore, some states require a doctor to notify the appropriate state agency (DMV, DHS, DPS, etc) when making a certain or prescribing certain medications. Having restrictions imposed because of such a diagnosis or prescription doesn't indicate a person isn't fit to do anything else.

2. The history you gave doesn't say much about the officials actual medical issue. The diagnosis of a concussion after he "blacked out" is a stretch unless he also has some history of head trauma. I'm not saying he does or does not have a history of head trauma, but it is entirely possible the concussion was the result of the fall after "blacking out". Ultimately my point is that it doesn't sound like anyone knows the cause of his "blacking out" (except hopefully the guy's doctor).

3. The issue may not be neurological in nature. He could be Hypotensive and forgot to take his medication on the days of the incidents in question. Diabetes is another possibility. Narcolepsy could be the issue, albeit some would classify this as a neurological condition. In any of these cases, a doctor might recommend driving (public safety) and/or work restrictions (not working alone due to concern of what could happen if nobody is around to help if he forgets his Ned's or falls and hits his head), yet give clearance to officiate because those same concerns don't apply to officiating.

From an officiating standpoint, I don't think it is unreasonable to ask him to be open with those of you on the crew about the details of his condition. For one, you can't help him if he has another episode. Secondly, if the episodes are preventable, the accountability created may motivate him to be compliant with his medications. Ultimately if he doesn't want to elaborate, you have to be clear with him about your concerns for his safety/health as well as the performance of the group. If he's still unwilling to help you understand his situation, I think you are justified in not wanting to have him on your crew.