I have the same problem when I use the IVtkTools_ShapePicker, I use the method to solute it.

when use IVtkTools_ShapePicker, you need construct map between vtk actor and OCC Shape, use IVtkTools_ShapeObject::SetShapeSource(shape, actor) func to construct. and your InteractorStylePick class set the picker need behind SetShapeSource, like this:

BRepPrimAPI_MakeBox box(2, 2, 2);
vtkNew<IVtkTools_ShapePicker> aShapePicker;
.....
create vtk data pipline
.....
IVtkTools_ShapeObject::SetShapeSource(shapeDS, actor);
InteractorStylePick->SetInteractorStyle(aStylePick);