I'm not really sure what I can and can't discuss about pass rates. In theory this is in the public domain, but in practise the information the CAA release to schools is often 'in confidence'. I only quoted these numbers because they have been reported elsewhere on the forum.
The CAA are required to operate in line with the Open Government Policy set out at
this website and must reply within a set time frame to questions from the public. The best thing you could do is ask them directly for the information, and refer them to the document above if they refuse.