Verified the document steps with the steps followed at https://bugzilla.redhat.com/show_bug.cgi?id=1749919. The Document look good.
Please ignore comment #9. sharding feature is introduced in "ceph 5" but the steps are updated in "RED HAT CEPH STORAGE 4 ADMINISTRATION GUIDE" Please check at- https://bugzilla.redhat.com/show_bug.cgi?id=1749919#c7
Checked the chapter - "9.7. Resharding the RocskDB database using the BlueStore admin tool" and looks good.