I don’t get how your issue and the backup go together. You can’t make a backup of a running database by just copying files. Roon, as far as I l know, doesn’t let you store a backup into the internal drive, the external drive you connect to your laptop instead of the ROCK and if you wanted Roon to store the backup onto a drive on (or connected to) your laptop then the laptop not seeing the ROCK would be irrelevant. Do you stop Roon Server from running before taking the backups you did in the past? If not then your “backups” are likely not working in case you ever need one. How to use the built-in backup function and avoid issues or the need to stop Roon Server (manually) from running first is described in:
How to resolve issues accessing the ROCK share over the network from recent Windows see: