The MKE operation customization (i.e. the supported set of operation parameters) has to be maintained manually unfortunately. This means that new operation parameters that get added to an NX CAM operations don't automatically show up in the MKE. It requires a bit of work on our side.
In situations like this, it's recommended that you double check the MKE customization. In the case of the Solid Profile 3D operation the NX Dailog column for the Cutting Parameters -> Corners dialog doesn't show any Smoothing parameters.
We'll need to add them to the customization_base.xml file.
Please send me a personal message if you would like to receive an updated version of this xml file which will give you access to these missing parameters.