Comments such as this are so depressing to those of us who believe in open and transparent government. To answer some of your specific questions, it's completely undemocratic, there's very little that can be done, especially by the public, but keep feeding the press frenzy as it can make a difference. The Clerk allowed the Councillors to behave in this way because it reduces public scrutiny of the Clerk as much as the Council. It appears to be predetermination, but that's poorly defined and rarely punished, particularly on minor issues such as this.
Public time is an important part of every agenda, as it allows the Council to explain its decisions, clarify misunderstandings, receive feedback, and identify issues that may need further involvement from the Council. How can a public dialogue not be Council business? Who do the Councillors represent? With the best will in the world, the Councillors can't be aware of everything that is happening on their patch, so the public has a role as the eyes and ears of the Council. Mature well-run Councils value this interaction immensely.
The only way to change this is at the ballot box. Start recruiting candidates now!