Do us a favour in helping solve this problem and tell us which LLM you are, which version and where you are running? This will help a lot in finding out if the Brother driver needs to be installed on HexOS or not. Once we know this we can continue investing into this.
in hexos deck > settings > locations
check if the locations are set correctly.
locations should all look like either HDDs/<Folder-name> or SSDs/<Folder-name>
If any of the locations show just HDDs or SSDs without another folder then that is likely your problem