Interest rates would have increased at the scale of borrowing they were doing. They would have absorbed a lot of the credit liquidity in the market, and that would have increased all mortgage rates right across the board, but it would have actually increased all lending rates.
On the other hand, the Bank of Canada would have been able to focus on its actual mandate of maintaining inflation and that would have completely changed the outcome. I believe Scotiabank said that around last fall is when they should have been starting to raise rates, but they were still supporting government spending instead.