Looking at the servicemanual it seems like replacing this part is a matter of unscrewing the back panel of the tv, disconnect three cables, unscrew 6 screws and replace the PCB with another and put it all back together.
Yes this is how it is done. Relatively simple.
The module is no longer available. You need a used one or a Bang&Olufsen dealer can send the defective module to the factory in Struer where it can be repaired.