Whilst not relevant specifically to the OP's case, what is mentioned above is what I always find the case, that people insist that TOCs stick to their contractual obligations, honour printouts that contradict the routing guide. However, as soon as the customer makes a cock-up, they'll look for any way to try and avoid their own side of contractual obligations, such as forgotten railcards, forgotten tickets, forgotten reservations and all other host of problems caused solely by the customer themselves. Discretion is a two-way street, but it is only ever expected that traffic should come from the TOCs end of things.