Why won't the BBC talk to the BBC about the Carol Thatcher 'golliwog' row?

John Humphry's on BBC Radio 4's Today programme this morning on the Carol Thatcher "golliwog" row which has led to her being axed from the BBC's 'The One Show': "We wanted to talk to the BBC but the BBC wouldn't talk to us."
This always sounds so bad on a programme that when it says "we asked a Government minister to talk to us but they declined" leaves the listener with the impression the Government or the minister has something to hide.
BBC management should realise not putting up someone to defend itself on its own news programmes is just very bad PR.
The BBC refused to put up anyone on BBC Radio 4's PM programme to defend itself against MP John Pugh's Early Day Motion motion accusing it too much "recession woe" in covering the economic crisis. It also refused to put up anyone on BBC Radio 4's Feedback programme to answer listeners' claims that business editor Robert Peston's gloomy reports were causing panic in the markets.