Renaming media files in rm9

up til now, I have used the following naming convention for my media files when using TMG:

100 Doe John Death certificate 2022_01_01 (where the number identified the person in the TMG database)

Having imported into rm9, the record number has changed for illustrative purposes to 200, therefore the filename would be 200 Doe John Death Certificate 2022_01_01. This keeps are the exhibits for one individual together and easier to locate.

I have over 5000 media files. Is there anyway to make the filename changes while maintaining the links and associations without handling each file and person individually?

Or is there an alternative to my naming convention that would require less work?