Whilst they may be able to find a link between the donors and...

Whilst they may be able to find a link between the donors and the terrorists via the money trail, it will be a different matter proving intent.
In the same way it is known that there is a money trail in Australia that links Centrelink with many criminals involved in illegal activities, the illegal drug trade being a prime example, child abuse another. If Centrelink continues to provide funding once it becomes known that the recipient is using the funds for support whilst continuing those illegal activities, Centrelink becomes complicit doesn't it?
I am being serious in making the link as I believe the welfare system is the source of the greatest threat to our society, terrorists being hardly a blip on our radar.