can you elaborate on what plots you're using and what value you're plotting?
also, have you done an energy balance? I noticed that your model has a very very coarse mesh. You may have asked for 1000 but you should check that you're actually getting 1000 on the face.
I would also start with everything being black bodies and then later on tune the model with other surface radiation properties like white body.
Try using Radiative surface >> Real Surfaces >> Symmetry for the parabola