Loose definition of "English" here...
"All words in the grid are common, English-language words used in everyday speech."
AMIGO: Common, yes. Everyday speech, yes. English, not so much.
Could someone modify the quoted sentence above so as not to mislead us puzzlers? Even a parenthetical addition like "common, English-language words (or non-English words commonly used by English speakers)" would help prevent some of us beating our head against a brick wall. ("It looks like 'amigo' but it *can't* be because the directions specify English-only!")