I misunderstood what you were asking me the first time, I'm sorry about that. I would tell them about the gospel of Jesus Christ, and that he is the only God worthy of their devotion, and to ignore the myths from their false gods. I would depend on the Spirit of God to support what I testify to them more than I would depend on my ability to disuade them their error.
Wayne, I think you have misunderstood the question even more here. Nogodsforme wasn't (if I recall) asking you what you would say to the tribes who believe in Eshu. She was restating a question which almost all of us have asked in some form or another, and which you have yet to answer.
The point is that these people DO believe in their god. Just as Muslims believe in Allah, Just as countless adherents of countless faiths have believed in their deities. Every bit as fervently as you believe in your version of God.
And for each of these faiths, there are countless people who believe that certain, completely natural occurrences are brought about by their god. There are countless people who have unswerving faith that their god speaks to them; that they have experienced miracles--coincidences every bit as amazing, and probably more so, than those you have related here.
You would say they are wrong. They would say you are. Each of you has your own scriptures backing up your claims.
Logically, you cannot both (or all) be right, but there is nothing that precludes you all being wrong.
The question is not one of prosyletizing to these people. It's one of recognizing that you are, in effect, no different from them