Was Breitbart duped by O'Keefe on the ACORN pimp hoax?

One of the lingering questions about Andrew Breitbart's dishonest attempt to help spread the falsehood that James O'Keefe was dressed as a pimp inside the ACORN offices, is was Breitbart himself duped by the masquerade?

Did he, in fact, not know that O'Keefe wasn't dressed as a pimp while meeting with ACORN workers? Instead, was Breitbart mislead by his protégé's undercover videos and only found out the truth much later? And is that why Breitbart's so reluctant to come clean about the hoax, because he'd have to admit that even he got duped, and that as the editor of the site that published the ACORN videos, even he didn't know the truth about their contents?

Any such an admission by Breitbart would be devastating. Because remember that for months he personally vouched for the videos. He's claimed that he's told “the truth” every step of the way about the ACORN clips. But what if we find out that Breitbart himself didn't actually know what was on the tapes. What if we find out that Breitbart, like everyone else, got fooled by the ACORN pimp hoax and mistakenly assumed, after watching O'Keefe's deceptively edited clips, that O'Keefe strolled into ACORN offices wearing the outlandish pimp outfit.

If we find out Breitbart himself was duped by the ACORN clips -- if he, as the chief promoter, didn't even know the truth about the contents -- then I think we can close the books on the whole ACORN video caper, as well as Breitbart's credibility.

UPDATED: The exit question: If Breitbart was fooled by O'Keefe, did he ever get an apology?