in Blender 2.82, then with ctrl+c & v copied the mesh back to my model in Blender 2.79
Interesting workflow.
I didn't know this is possible. You never stop learning. I tried it but it does not make a difference for me, appart from the fact the 3D-Viewer in 2.79 is generally not as good as the newer versions.
Are you exporting from 2.79 with FBX or with the Merk-AddOn? If you use FBX and want to get more into Blender I would recommend to use 2.8 or higher the earlier the better. They changed a lot in the UI/handling (will take some time to get used to it and in my opinion they improved a lot).