Best way to draw an array of objects

yes you are right, i didn't try to draw the mesh right after tesselatation.

the next step is

        for (int i = 0; i < mesh.getVertices().size(); i++) {
            vboMesh.addVertex(mesh.getVertex(i) + pos);
        }

drawing vboMesh doesn't work here. something get messed up. Following the mesh vertex array, i would have thought they would be copied in the right order into vboMesh... but it doesn't obviously.

So there is no need to get the tesselation if i have to reorder the vertex afterwards. Using polyline as you previously suggested is the same (without tesselation)