For completeness later in the thread Flush test data from Bahmni/opeMRS @binduak advised "You can directly download the file using wget in guest machine ( Bahmni server ) and run the above mentioned restore commands.
wget https://github.com/Bahmni/bahmni-scripts/raw/master/FreshDb/v0.86/openmrs_backup.sql.gz" this was done and the data deletion apparently worked fine.