Who decided to divert $50 million to a G8 slush fund?

According to the Office of the Auditor General, one of the unsolved mysteries of the G8 legacy fund is who decided to divert $50 million into a slush fund?

“We made simple investigations into why it was $50 million, but there was really very little information available. We had asked, through the normal course of doing our interviews, the departments that were involved in this, but they had explained to us that it was really not a decision that was made at their level.”
– Wendy Loschiuk, Assistant Auditor General, Standing Committee on Public Accounts, October 5, 2011

So who decided on diverting $50 million? Here’s what Tony Clement told local mayors in Muskoka:

“Budgets in addition to the basic G8 Summit Management Office Budget must first be determined by the Prime Minister's Office.”
– Local Area Leadership Group Minutes, November 7, 2008

But when asked in the House of Commons about the involvement of the PMO, John Baird came up with an alternative explanation:

“The $50 million was allocated in budget 2009 as part of Canada's economic action plan.”
– John Baird, Hansard, October 7, 2011

Just one problem: Budget 2009, Canada’s Economic Action Plan, makes no mention of a G8 “Legacy fund” or “Muskoka”.