In the answer to the other question:
"You can use a different colormap and a different method for calculating the Z-values, if you need more distinct color differences."
- Change the colormap to define the colors you want to apply. For two colors this is basically just cmap=[r1 g1 b1;r2 g2 b2]
- Set the Z-value of your dataset to assign these colors to elements.
In the previous answer, the Z-value was selected randomly. From your attached figures, it appears they are still assigned randomly. You need to change this line of code and assign Z-values by your criteria.
In short: colormap sets the palette, but you paint the segments through the z-data