The question you are putting to me is huge. I worked in Africa for 19 years. As you can imagine, the problems were similar.
The mechanisms Canada uses to execute projects in Haiti ensure, in a reasonable way, that the funds are spent as Parliament intended, that is to say to assist the poor of the third world. Very rarely in the course of Canadian history and within the framework of CIDA budgets were significant amounts diverted from their primary objective or used for corruption. It would be quite easy to verify those facts.
Whether or not our projects are protected from corruption, this is irrelevant if the society within which we are implementing them is completely dysfunctional by reason of generalized corruption. What can we do to fight against this corruption? In my opinion, the only thing we can do is to force transparency through democratic avenues. There are other ways of making people aware, but I believe that the most important thing is to educate the public and to force people to be accountable.
In Africa, I observed some very interesting phenomena. As soon as a dictatorship fell and a more democratic government took power, transparency would suddenly result in the truth coming out.