Resolution:
It is possible to export using the catalog publish with "dbDump" set to ‘Y’ in "UpdateEventStartSync" activity of the wfin26catsynchv4.xml(Publish workflow) where the output of the catalog publish will have all the attributes including the contains populated in it.(If the contains of the MCT_XXXX has any value in it)

Once the output file is generated, the relationship can be modified accordingly and data can be re-imported into the master catalog.

Note: This will work well only if the initial data relationships is created using the import, where the entry into the ‘contains’ attribute will be done. It will not get the relationship details from the RELATIONSHIP table.