Look also into the requirements of Annex II (or V). On several places reference is made to control various processes. Any process shall be assessed on hazards and risks for the patient/user (ER 1-4). And validation of processes can be used as evidence of control of processes or steps thereoff. Other options are 100% QC inspection (or sampling based on AQL etc).
Look into the former GHTF documentation on process validation for terminology and methodology.
Technically, validation is only mentioned in regard to sterilization, software, and virus elimination.
But: you are not going to win this fight with your Notified Body