OT- 3D Print Problem

Friend of mine who owns PolyJet 3500 is having unusual problem printing crest created in ZBrush. On each try, the flat plate comes out good but all the art-work on top of it prints out double. It’s like looking at stereoscopic version. I opened his stl file in rhino, besides few minor non manifold edges which I fixed there was nothing out of ordinary. Solid mesh. Author also checked his ZBrush file and can’t find anything wrong with it. 3D printer BTW is fine because other parts grown at the same time came out fine.
I was hoping maybe somebody on this forum run into similar problems and already found solution. His project is under quickly approaching deadline…
Many thanks

The Rhino mesh repair wizard generally does a good job of highlight errors in the mesh but you may wish to use a tool such as MiniMagics from Materialise to review the stl files. It analyses the files and reports errors from an additive manufacturing stand point.