In the first train/helicopter sequence, exterior close-ups of both the front and rear of the train show baggage sections, with few windows and a wide door. But in the second train/helicopter sequence, the same cars look like ordinary passenger cars, with regular windows all along their length.
While the escapees from the tunnel are digging rock away, the exterior is very dark, moments later as they escape the tunnel, it is daytime.
When the helicopter pilot is removing the stones from the collapsed tunnel, the rocks he lifts up weigh close to nothing. Real rocks of that size would weigh close to a hundred pounds if not more and would take serious amounts of effort to move.
The Rocky Mountain Express train which departs from Vancouver British Columbia and rides through to Alberta does not resemble the train in the photos by any means. and is actually called the Rocky Mountaineer,
There is no Bryant Tunnel located anywhere in the Rocky Mountains in British Columbia or Alberta. The Bryan Tunnel does not exist.