The agency won the print and rich-media banner categories for its work on KY, but came under scrutiny when the client said it stopped working with DPZ three years ago.
Johnson issued a press release on Tuesday to the Brazilian press saying it was not aware of the prize-winning ad and that it was produced "without the involvement or approval of any of its staff".
It added that Interpublic Group of Company-owned McCann-Erickson Worldwide has held the KY work in the Brazilian market for the last three years, not DPZ.
On Wednesday, two of the International Advertising Festival's judges asked the event organisers to launch an inquiry into the allegations.
Following an investigation, the following statement was issued: "After a thorough check conducted by [newspaper] O Estado de Sao Paulo, the official Brazilian representative of the festival, it was concluded that DPZ's top management was caught by surprise on this issue. It seems that a junior creative of the Rio de Janeiro office took a regretful initiative when entering inappropriately these ads."
The debacle could turn out to be the first scandal of the Cannes festival, which has tried to ensure that ghost ads such as these -- where an agency enters work that has never actually run as a campaign -- are not entered into the festival.
Various advertising awards around the world have been hit by scandals where winning ads have never actually been used by clients.
Most recently, Ogilvy & Mather was revealed to have entered work done for The Samaritans and for the UK government in the ±±¾©Èü³µpk10 press awards that had never run. The agency later apologised.
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