I mean, do they get something when they do not reveal themeselves to the public? For me, if they are a business entity, revealing that they won the auction can actually help them.
The latest was that the BTC were already transferred to each of the winners.
How revealing themselves could help them? They already won the auction, have the coins. If they were business entity as you suspected it will actually be beneficial to them that they hide the way they acquired coins. Anyway I really does not matter much for bitcoiners who won and we may never know that.