You're correct you've got a Bavaria C Business KE-92ZBM manufactured by Pioneer. There is no serial number code calculators or databases in existence to provide code from serial number for this radio.
I expect the code will be stored electronically in eeprom memory P2100R.
Unless you know or have experience in reading eeprom memory using eeprom programmers, your solution will be the services of a radio decoder in your area.
sorry.