Hi Mike and Grace,
Just a word of warning, in case you weren’t already aware: the Data Approvals sub-app has just been removed from DHIS2 (release 2.33), so any approvals you implement now will shortly be obsolete:
As far as I am aware, this feature was removed without any planning or advance notice to the community. 
Two of the national HMIS teams I’m working with have been planning to implement Data Approval workflows, but given this sudden change, have decided to put those plans on hold.