He certainly didn't learn English here in the US then! I remember a man from the an Arabian country that worked in my previous job that learned "English" from Louisiana oil rig workers. Every other word he spoke was the F-bomb, and much of the rest was Creole Cajun slang. I think it was the strangest linguistics I've heard in my life!
Jimi, Robert, and Dee really do speak excellent English from what their videos reveal.