Here is a design for a 3D-printable adapter to simulate two green struts sharing a pentagonal hole in the Zome ball. It must be printed using a good laser-sintering printer. The STL file will soon be available in my Shapeways store.
The adapter itself acts like two G00 struts and attached Zome balls. Adding a G0 strut (as depicted) on each arm of the V shape yields effectively two G1 struts sharing a single hole. This is the narrower angle of two possible angles for such a configuration.