UPDATE no.2. Changed VIN in 528i CAS. Car starts OK, many fault codes are now coding related, but I also have now variant coding in 528i DME...strange cause it's already hard-coded in OL option and CAS4 is from the same car with the same power class.
Would VIN difference between DME and CAS affect power class? Food for thought.
I want to thank AUTOHEX_BMW, Findlaybaum and Tibibond for their interest and helping me pulling the ISN from both CAS4.