I do not think the colour of the wood is much of a factor in identifying the origin with this club. I think the form is so convincing. Traditional "tribal" weapons tend to follow a standard form but in that there are regional and personnel variations. Here are two of mine of different wood. I also add this picture from " Amazonien Indianer der Regenwalder und Savannen , Museum fur Volkerkunde Dresden " Here is a similar style variation to the pommel and variation of plant fibre wrap to the common form. Your club may have had a wrap in the past, they do not take a lot of handling and would be replaced. The club from the Dresden Museum was collected from the " Ira'amranh-re " In a geographic region there local variations. It is a really nice looking club.
It would seem that the Ira'amranh-re are a sub-group of Kayapo or A Kayapo group on the Ira'amranh-re river, it is hard to get more specialist information.
I have just found on the web that there are four sub-groups of Kayapo; Gorotir, Menkragnoti, Metyktire, Xikrin. So it looks like the Ira'amranh-re may be a different group or more distantly related people.
This German web site link;
https://freie-referate.de/erdkunde/457-2 does state that the Ira'amranh-re are a sub-group of the Kayapo.
Other unrelated groups also live in the Tocantins river region like the Karaja and use the same form of club.