Keynote: William Kahan: The content of that page is Vitek’s keynote.
I believe both keynotes are in the same link - first Vitek’s and then Kahan’s.
Yes, then both keynotes are mislabeled. 
No, I don’t think so - the video ends after Vitek’s keynote. I can’t find Kahan’s and the video embedded on the talk page (here) doesn’t work for me.
Interesting - when I watched the Vitek talk, the Kahan one was in the same video immediately afterwards. Must have been edited since I watched it.