And I forget to add these images:,,  
There is no more certainty that the image used in the article is him then any other image which purports to be him. The New York Times can make any statement they like regarding this, it doesn't mean that they are correct. Far more reliable sources use many images depicting him than just the one used in the article stating it is the only one known. This article states that a different image is one of the few images known to be him  while this states that the two images used by the U.S State Department, of which the one from the article is from, are not of Omar . So there is no real consensus over which images are of him or not, nor of when each picture was taken. This article describes the current image used in the article as being taken from the late 1990's , in contrast to the Vanity Fair article which stated it was taken in 1993. I'm not saying the image is not of him, but I am saying that stating it is the only confirmed photo or the only known photo of him is probably not a correct statement. It might give readers the impression that it could be true, when it might not be.