I would expect that deleting a VMFS volume and reformatting it removes all references to files that existed on the volume before the format.
That assumption either is wrong ??? - or the format process works very strange.
Why would it keep references to files that - if I trust Datastorebrowser - no longer exist ?
To reproduce do this:
make sure datastoreX has a few files and directories
cd /vmfs/volumes/datastoreX
hexdump -C .sbc.sf > /tmp/sbc-pre-format.txt
now delete datastoreX and reformat it
in Datastorebrowser it should look blank - only the .*.sf are visible
repeat the commands
cd /vmfs/volumes/datastoreX
hexdump -C .sbc.sf > /tmp/sbc-post-format.txt
examine the file /tmp/sbc-post-format.txt
it still has references to files that no longer exist