I don't mean to diminish the poignancy of the message in the ad or the dialogue - it IS a powerful piece - nor do I wish to diminish the sadness of Robin Williams' passing. But, I have doubts that he actually had much active (or any) participation in producing this ad, like the story suggests (saying it was his "final production").
It's very likely that the team which put the ad together (of which I doubt Williams was part of) simply lifted the original audio from the film and spliced it into the ad timeline in Final Cut Pro. Of course, Williams likely got a nice royalty check, but I really doubt he re-recited the monologue, or had created sway in the ad.
Still, a powerful message, and I'm sad to know he's gone.