You cannot buy perforated currency booklets.

It's reasonable to be suspicious about the latter, especially as I suspect Woz didn't start the interview with "I bought the currency sheets then had them turned into this" - and anyways, by that time the agent had a checklist to run through, likely including the passport numbers etc. as mentioned in the article.

Even knowing that the bills are being sold in sheets, you wouldn't want to be the agent who let someone go who was doing everything exactly as Woz did except for getting the currency sheets from the guy printing the North Korean superbills...