First, a private foundation, like the Clinton Foundation, is not required to take competitive bids, unlike the government. They can hire their friends.
Second, this deforestation issue in Haiti has been in the news for decades. It has presented a grave problem for Haiti from both environmental and economic perspectives. The mountainsides were eroding. Large portions of Haiti's land were not being productive in producing food, despite food scarcities in the country.
And no one was fixing the problem.
The Clinton Foundation did something. Perhaps it was suboptimal, but at least they did something, which was more than other people were doing.
Also, the fact that Bill learned about a possible solution to a longstanding problem during a paid speaking engagement does not mean that he is corrupt. He saw a possibility of synchronicity and he acted on it. This is a good thing.
By contrast, Trump was using his foundation as a personal slush fund.