From what I’ve read, and hopefully others who know more will respond, Stevens was the Ambassador in title, and did not usually hang out in Benghazi; but had an appointment with a Turkish fellow that day (don’t know title of Turk). So Stevens went to Benghazi that day specifically. The survivors have been prohibited from telling anyone anything, haven’t you read some of those articles? They have been controlled, made to sign confidentiality papers, kept separately from each other, and some have been given fake names.
I’m pretty sure it was the Turkish Ambassador. This is another little piece of the puzzle that needs to be examined.