Foster is wrong. There's nothing morally complex about what Riefenstahl did as Hitler's favorite filmmaker. The only thing complex is Foster's confusion on this issue.

Nothing that is morally wrong can be politically right.

There is nothing politically right that is morally wrong.

Nothing is politically right which is morally wrong.

There is nothing politically right that is morally wrong.

Holocaust-deniers are not scholars or researchers -- they are bigots who try to hide their anti-semitism behind the mask of fake scholarship. For a U.S. government report to call them 'scholars' gives them the legitimacy they desperately crave but do not deserve.