Just to stir the pot.
Why not take a "used cluster" with different immo data.
-Read the stock eeprom from it.
-Put it in your car and adapt it with VCDS.
-Read out the new altered/adapted eeprom.
-open both eeproms in a hex editor and see what areas were changed.
The you will be able to determine is there are indeed more changes/encrypted areas then meets the eye.
It's a good idea and I wish I could do that, but the trouble is that my car is IMMO 2 and so I cannot do IMMO 3 cluster adaptation with my car. That's actually what I first tried to do when I got this IMMO 3 cluster as I was following the Rosstech instructions for matching the cluster to the car, then I realised as my car is IMMO 2 it wouldn't perform the matching (channel 50 doesn't exist in the adaptation menu).
Thanks for your suggestion