There were also people who worked for T-Mobile who 'won' a chance to be in the advert through internal marketing.
At 11am, the station would normally be fairly empty. I do think a lot of the people there, if not most, were in on it - including the spectators watching from above.
They had a number of hidden cameras, but surely in these times they need to get people to sign release forms, so even those people above must have been pre-warned.
Goodness knows what happened to the trains leaving on or around that time. Did they experience some sudden delays?!