Is there a possibility to add a LOD to a model manually in MED?

What I would like to do is to combine a manually created "Model A" which is high-poly as LOD 0 and another manually created "Model B" which is low-poly as LOD 1.

Both models were created in an external animation software.

I would need such a model for casting shadows. LOD 0 should appear visible and LOD 1 should cast shadows while being invisible.