I am sorry the CAA has not communicated more comprehensively but you have had two seizures so I am not surprised they are not happy. Without knowing what caused the second seizure it is impossible to give you further advice as some triggers may or may not potentially recur. You need to inform them of your full history if you have not already done so, and ask what you need to achieve a) to obtain your medical within the 5 years and b) what you need to demonstrate at 5 years. There is no point wasting money on seeing doctors if the regulator is intransigent.