I'm not sure the link between Stagecoach and Scot Airways is that secretive. As Chief Executive and founder of Stagecoach plc, Brian Souter declares that he is also Chairman of Scot Airways.
I know a few ways of becoming Chairman. Mr Souter would easily qualify on the strength of his transport and business experience. I would have thought he also has the means to invest in the business. I'm sure there are other reasons besides.
Richard