As far as I can tell, your wrapping is written manually for each VTK class. VTK has a very large number of classes and no stable public API, so this would be a lot of effort in the long run to wrap all classes and keep it up to date.
Have you looked into vtkWrap* classes and logic that parse headers and perform automatic type and function translation to the target language? That would be a more robust approach to build automatic rust bindings.