I would expect Class 92 to get a flea in his ear if he tried to get this info from Northern or any other normal franchise
As with any private company, if they say it is 'Private & Confidential' it is private & confidential - whether its Tescos, Stobarts, an insurance company, a bank or a TOC
If its the UK (or local) Government department/company like ECML, the Freedom of Information request should result in getting the requested information
Brian