Delete troublesome files from unmounted external drive

Running 10.13.6 with an external 8TB seagate drive.

The drive will not mount. Tried all the usual things. Disk utility sees it but won't mount it.

First aid responds with unable to fix it.

Ran fsck_hfs with the result:

/dev/rdisk3: fsck_hfs started at Mon Aug 10 21:24:43 2020

/dev/rdisk3: /dev/rdisk3: ** /dev/rdisk3

/dev/rdisk3:    Executing fsck_hfs (version hfs-407.50.6).

/dev/rdisk3: ** Checking Journaled HFS Plus volume.

/dev/rdisk3:    The volume name is Backup2

/dev/rdisk3: ** Checking extents overflow file.

/dev/rdisk3: ** Checking catalog file.

/dev/rdisk3:    Incorrect block count for file .store.db

/dev/rdisk3:    (It should be 6679 instead of 7529)

/dev/rdisk3:    Incorrect block count for file 2.indexPositions

/dev/rdisk3:    (It should be 4097 instead of 73866)

/dev/rdisk3:    Invalid sibling link

/dev/rdisk3: (4, 737097)

/dev/rdisk3: ** Rebuilding catalog B-tree.

/dev/rdisk3: ** The volume Backup2 could not be repaired.

/dev/rdisk3: fsck_hfs completed at Tue Aug 11 09:49:54 2020

I have left this running for 3 days with the same result.

I believe that the files .store.db and 2.indexPositions are the ones corrupted

The questions are:

If these files are deleted will that resolve the issue?

Is it possible to delete these files on an unmounted disk?

A long shot, I know, but worth the inquiry before I erase the thing!

Cheers

Tim