Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I understand your concern.

There can be many causes for seizures and for that reason a visit to a neurologist is certainly advised. They can be due to stroke, tumors, infections, metabolic changes, autoimmune conditions, drugs etc. At times no cause can be identified, but that can be said only after tests about the cause have been done which is particularly important in someone his age when it is atypical for seizures to appear without an identifiable cause.
So there are several tests which should be done to that purpose. I suppose he must have had some basic blood tests for metabolic causes and infections in the ER. Most likely he must have had some type of brain imaging like CT as well. If they found nothing wrong it is reassuring in excluding threatening issues like brain tumor, he should feel heartened and encouraged to meet a specialist to find other treatable causes. Among tests to be done are an MRI and an EEG, depending on what tests were done in the ER some other blood tests may be required as well. Management will depend on the results, if a cause is found it should naturally be addressed accordingly, it is hard to make predictions without knowing more about test results.
Of course I realize it is hard for you to make him accept that he should ask for help. I am not sure how I can help about that perhaps reading this answer will help change his mind.

I remain at your disposal for other questions.

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Brief Answer:
Read below

Detailed Answer:
Keppra is one of the most widely used and safest antiepileptic medications nowadays but in some patients it may have side effects, including some character changes, hostility, depression, anxiety etc, so if that is judged to be the case it should be switched to something else, there are plenty of other alternatives out there which could be used with better results. So he should understand that failure of one drug (or side effects) doesn't mean there is no other alternative, many antiepileptics these days, different ones work better in different patients. With 3 seizures though he shouldn't be left without treatment, that is for sure.
However as the ER doctors suggested that can be under the guidance of a neurologist. The choice depends on seizure type, EEG findings, possible findings on MRI etc. Even if first EEG was normal it may be repeated, a single EEG captures abnormalities in only about 50% of patients, but repeat testing increases the chance of capturing epileptiform abnormalities. So evaluation by neurologist is required to choose an appropriate alternative to Keppra.

Let me know if I can further assist you.

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Brief Answer:
You're welcome

Detailed Answer:
I hope things will work out for the best.

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