This would be less silly if what you were pretending is so obscure and nuanced was not actually as plain as day.
I took your invitation to reread, and only needed to go as far as the second paragraph: "In some shots, the teens appear to be shouting “build that wall, build that wall.”"
This is false. Not an opinion, not a narrative, a plainly false statement.
My "contradictory sources with at least the same level of journalistic respectability" is any of the videos of the event themselves, is that a credible enough source for you? The full-length video was available at the time of the writing of this article and Vox did not make any effort to verify what they wrote against it.
They lied, period. This is not that difficult to understand. Do try to keep up.