This story got very weird in the last two chapters. In those chapters (this is the last one), the story jumps forward to the present with a group of archeologists traipsing through the Amazonian jungle in search of a tomb or a massive structure. They run across a group that has found a tomb and is searching for a massive diamond. Here, both groups run afoul of a local tribe who slaughters them all, leaving an uncertain ending.

(Heavy Metal issue #64, July 1982 – Page 70 At the Middle of Cymbiola by Renard and Schuiten)