Continuity mistake: In a close up of the tar wagons before James crashes into them, James disappears.
Continuity mistake: James leaves Elsbridge Station with the brake coach at the rear. When James arrives at Knapford Station, the brake coach is in the middle.
Answer: Butch the breakdown truck must have pulled Gordon's tender all the way up the rails so the breakdown train can reach it and also Butch helped to get Gordon close to the winch.