"they propose a shoot of me playing pianos on the street around the city " (to me, not necessarily a music video shoot)
"I've been playing "I Don't Want To Be a Bride" for our little video shoot all day" (still, not a music video. Could be promotional, could be bonus content, could be part of a "pleased to meet you" part two)
"As luck would have it a 42-piece children's choir was singing" --hence, no planned choir, hence, no storyboard for a musical video as I am assuming there is some sort of planned concepts for a musical video/vision.
To me, this doesn't seem like a musical video shoot, just a video shoot for other purposes. I could be WAY off, I don't presume to be the authority on anything, these are just my thoughts. I'm very doubtful on the rumors of a video shoot, even though friends of friends have said they are in the video -- I mean, I could tell you my friend Elizabeth has a friend named Windy who has a race car that was in a commercial. And while those people I've named are very real people, you're taking it from me that what I say is true (is it?).
Last time, when the Carousel video was being shot there were things going around Twitter from the people actually DOING the shoot, like the camera man and the person doing the editing. We have none of that, just one rumor.