Miller said on Thursday he had “never knowingly taken any banned substance”.
Khan takes on Crawford in New York on Saturday night.
Business as usual for Anthony as he prepares to make his debut in the United States.
Promoter Eddie Hearn said the Briton was “devastated” after a fourth-round knockout in Los Angeles.
The 27-year-old’s purse has also been withheld.
Katie Taylor beat Brazilian Rose Volante to add a WBO strap to her WBA and IBF titles.