Most likely with an impact that severe, the passengers were either killed or incapacitated on impact, especially giving the fact none of the others were noticed trying to escape when the bystander broke out a window.
The front doors do have easily accessible manual releases on all of the models.
That being said, for the ones 'equipped' with the emergency feature for the rear, it is a manual release cable buried under the speaker grill, which is something very few passengers would know about in the first place, much less have the presence of mind or physical capability to remove the speaker grill and find/pull the cable.