Actually I'm surprised by that Amy Camus story - I've always known she was Peruvian, I guess because I live here in LA, her home, where she often performed throughout the '80s and '90s.
Actually, that's how I found out about here - I read a newspaper review of her show, comparing her wild vocal pyrotechnics to such
then-contemporaries as Nina Hagen, Kate Bush, and Lena Lovich. I thought: "Wow, my kinda gal!"
But I can see how rumours of hoaxes could start - it was pretty common in the exotica era, e.g. Korla Pandit and Chaino were black Americans posing as Indian and an African "savage", respectively.