I personally hate BA and have sworn never to fly them again.
However, there is legislation in effect which severely limits BA's ability to share data without the informed consent of the person concerned. This legislation contains additional provisions for sharing this data with entities outside of the EEA. I think that would be you.
BA's legal team clearly has instructed BA staff not to break the law and may also have issued specific instructions on the release of passenger information to third parties.
Don't blame BA, it's not their fault. If you want to blame somebody, look a little closer to home.