If you're talking about injection points, you're missing the point. Yes, that's how Cantillon himself talked about it but that's not what Hayek talked about.
Monetary policy lowers the interest rate and raises the price level. That's the point. It will also change the price of more specific kinds of assets to do that, but let's just stick to the interest rate and price level. Those are market signals. Forget the injection effects themselves - loans made in a lower interest rate environment are going to be made to a different sort of borrower than loans made in a higher interest rate environment. Hayek is very concerned about whether investments by that different sort of borrower are sustainable or whether the changes to the capital structure are ultimately unsustainable or impoverishing.
My post from a couple days ago on this point is here.