What would cause uncertainty in a doctor re. a diagnosis of epilepsy?

May be difficult: The doc needs to consider whether the symptoms fit a classical epilepsy diagnosis, or even "non-epileptic seizures", if this is a fainting spell, whether it is hypoglycemia, a cardiac arrhythmia, or even a psychiatric issue. Especially difficult may be frontal lobe szs or complex partial seizures. An eeg may confirm, and other tests may be necessary. Sometimes not so straight-forwards.