Why was Lupita Nyong'o given a 'worthless' dress for the Oscars?

The $150,000 dress Lupita Nyong'o wore at the Oscars has been discovered after it was found in a hotel room because it had no value. The question is, why was an Oscar winning actress allegedly given a worthless dress that even thieves would not want to steal?

Surely a brand would want to provide a dress that had some physical value rather than giving an individual a fake just for the cameras. If it is confirmed that the stolen dress is in fact worthless and that the pearls are not real, it seriously undermines the credibility of the designer.

Lupita Nyong’o in '12 Years a Slave'

The whole point of making the dress is to show something of unique value at a very high level to millions of people. The marketing potential around that is huge with the Oscar red carpet, but what we have here is a potential PR disaster if it is in fact confirmed that Lupita was knowingly given something without tangible value. What kind of message does that send out to people who care about fashion, or care about the dignity of this woman for that matter? How does that make her look?

I'm not going to jump to conclusions without seeing the full outcome of the whole dress ordeal, but I'd like to see a marketing department trying to explain why they thought it was a good idea to give a fake product to a celebrity.