I'm also very cautious about manipulating our complex environment without really understanding what is going on. But in this case, after careful reading of the post (where it is explicitly mentioned to keep healthy mosquitoe populations in the lab until sure) and Wikipedia I tend to agree that this would reduce human suffering without noticable environmental impact. Apparently there even have been studies to the effect:

Studies have shown that this process has been very effective in preventing sleeping sickness in people who live in the area.

I still upvote your post because you do name a few points that are all not addressed by the article. And there could be more which are plausibly problematic.