I looked into this more deeply and I’m seeing that CreatePolyhedron triangulates the faces using the first index given for the face as the first point in each triangle in the face. So, the assumption that vertex order doesn’t matter only holds if the face is convex. If the face is concave, like in your playground, then the order definitely matters, and there are some concave shapes that aren’t even possible to achieve with CreatePolyhedron.
I think my original suggestion of using CreatePolygon for each face and then combining the resulting meshes is maybe the best solution for concave faces.
cc’ing our geometry expert @Evgeni_Popov to fact-check this for us.