That link says they started "last October" and is dated February 2017. It covers 95 people. That's a very short period of time, quite sparse on details, and a small group of people in an isolated environment. They're also not taking money from people in the community to redistribute.

Put plainly: It's not surprising at all that one can take a lot of voluntarily-given money and distribute it to an impoverished village in Africa, resulting in them being happy and saying they're seeking work (in the short term). Normally, though, that's called "charity" rather than a UBI experiment, and even UBI opponents will acknowledge the likelihood of that happening.

Thanks for the link.