Community School Governing Body meetings, which under Local Management of Schools make all the really important decisions the head does not make, are held in public
Not always. There is no legal requirement for them to be held in public. It is up to the governors to decide whether or not to admit the public to their meetings.
Academy Trusts can, and do, refuse access to Trust Board minutes, even when made as an FOI
There are only limited grounds on which they can do so. The same grounds also apply to governors meetings. It is, of course, true that some of the exemptions are more likely to apply to minutes of a Trust board meeting than minutes of a governors meeting.
In fact getting up to date information as to who is on the Board of an Academy Trust can be difficult
You can always get an up to date list from Companies House or, free of charge, from various websites such as duedil.com.