Hi Paul,
If you are still keen to apply for a medical then one possible avenue to explore would be to claim that your son had a head injury as a result of the electrocution. This would then put your son under the post-traumatic epilepsy section of Australia's DAME HB:
http://www.casa.gov.au/manuals/regul...e/080r0205.pdf
However there are strict rules as you can see in the recertification sections with regard to being off the anti-convulsants prior to any assessment by CASA.
Unfortunately true epilepsy precludes certification on the whole.
If there were only one or two seizures associated with the original event then you may be able to make a case for recertification if off anti-convulsants. However a fit off the medication will have implications for driving etc... let alone flying.
Hope this helps