I am not seeing the reversed faces issue. In the graphic below you can see your dwg imported into SketchUp 2017, 2018 and 2019. The face view setting has been set to Monochrome in order to see the face normal orientations. All the imports show the normals facing outward and the non-normals (blue) facing inward.
If you are not seeing the same, perhaps upload a screenshot so we can see what you are seeing.
CD