(at around 1h 15 mins) On the far right-hand side behind the wall corner, we can see what turns out to be Hugh Fraser (Captain Hastings) waiting for his cue. There's also a shadow on the wall at 1:15:32 that seems like a crew member holding their arm up as a signal for him to go.
As Miss Lemon walks out of Blackridge Station, a crew member is visible. He's standing in the passageway as people walk by and is wearing a short-sleeve shirt, modern khaki pants and a gold watch on his right wrist. A walkie-talkie is attached to his belt.