[illuminate]

"Umm, another possibility is that he learned Castilian, and the people in your office grew up speaking some Latin American version."

Someone fluent in conversational Spanish would still be able to speak the basics with a sympathetic, if skeptical interviewer.

[toomuchcoffee]

Yeah but quite often people are thrown off balance when encountering other native speakers of a shared, large language group (but speaking a different accent or dialect) for the first time. That's all I'm saying.