Unfortunately, regardless of the reason that you want this information regardless of the fact that the organisation exists to help people with the same disability, they are not under a duty to give you the addresses of the other branches.
However whilst that is the case, legally, this is most unlikely to be a breach of the Data Protection Act if all they are doing is giving organisation names and addresses and there is no common law duty of confidentiality. It would be different if they were secret organisations or you are asking for details of members but as you are not, there is no legal problem which I am aware of to stop them giving you those addresses.
Unfortunately, if they steadfastly refuse, not even a court application could make them give you the details. Sorry
With regard to the application, you are free to ask whatever questions you like and if anyone who is applying doesn’t like the questions, they are free not to attend one of the trips.
If you are not registered with the Information Commissioner as a Data Controller under the Data Protection Act, then you need to be. It is only about £35 per year and might seem rather academic but it does stop people reporting the breach if they decide to be a do-gooder on a bit of a mission.
Can I clarify anything for you?
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