I think perhaps you missed my point. It is very difficult to actually identify someone correctly the way that it is done these days, and just for reference, the person I had to identify smiled at me and spoke to me for a few minutes before endangering my entire family, and I thought for sure that I would never forget that smiling face. Until I had to go through the identification process, where, in the photos that you can only see once, briefly, the potential suspects are not smiling, and they are nearly impossible to positively identify without direct comparison to see which one looks the most like the image in my head. Although, again, I did not have the media to help me recognize the face of evil again when I saw it by burning it into every tv screen and newspaper headline for weeks.
And also, again, logically, even if she had a photo of them as the last person to see TB alive, or video footage of them leaving together, it does not mean that DM killed him, only that he was the last person she saw TB with. You could be the last person to be seen with someone who died, it doesn't make you a murderer automatically. We haven't even heard DM's side of the story yet, but most it seems have fully condemned him without ever hearing a single word from him. Catch phrases like "the face of evil that smiled at her" are great at swaying people's emotions, but the hard truth and facts acknowledge that eyewitness testimony is highly overrated and often flatly wrong. (The Innocence Project reports eyewitness misidentification occurs in approximately 75% of convictions that are overturned).
Eyewitness testimony - Wikipedia, the free encyclopedia