Your question is a bit confusing to me, but I'll give it a shot....
"Did he walk to the station?" really isn't relevant in this situation. If the train had already departed by the time he'd arrived at the station we can only presume that either he arrived late or that he arrived on time but the train left early.
As for three relevant questions, are you looking for questions relating to why he might have missed the train? Or reasons why the train left early?
For example, I guess you could ask:
Should he have left for the station much earlier than the scheduled departure time, allowing for such delays as traffic congestion?
Can he either catch a later train?
If he decides to use another mode of transportaion can he be reimbursed for the ticket he was unable to use?
I don't know if I've answered your question properly because, as I mentioned, it wasn't really phrased very clearly. But I do want to mention that I visited Skipton once many years ago while visiting the UK - toured the castle, stayed in a B&B that was only a few yards away from the railroad tracks (that's a story in itself).