Quite frankly, I can't help but wonder if you could work in something similar under existing U.S. laws.
If the "denial" incorporates slander or liberal, it could easily be seen as legally actionable.
And let's face it. Some of the "stories" you hear about denial often talk about how the "Jew" created this lie.

Obviously there are some grey areas. If no mention of who was supposedly responsible for the claimed "fraud", there is no target for the slander/libel.
Also, I suspect it is easier to perpetuate such libel / slander if you avoid naming names but instead blame the general group, although I can't help but think such a cop-out should not be allowed.
It's hardly any less slanderous (IMO) if you are "vague" about it...