Question:
How to rename DirectAudit Database?

Answer:

To rename the Management database and the Audit Store database(s), it is essentially performing database migration without actually migrating the databases to a different server. The details steps is included in attached PDF file and see more details in :
KB-2727: How to migrate SQL databases associated with a Centrify_DirectManage Audit 3.x installation from one database server to another.

Summary of steps to rename Management database and Audit Store database(s),

1. Rename all the databases using SQL Management studio (might need to take the DBs offline before you can rename them).

2. Update the rows in dbo.ManagementDatabase and dbo.AuditStoreDatabase tables using SQL Management studio (value for the column "Database" needs to be renamed).

3. Using ADSIEdit.msc, update the DA installation SCP (specific instructions are in the PDF attached to this KB).

4. Reconnect to the installation using Audit Manager console and re-sync the publication information.

Note:
Renaming Both the Management database and the Audit Store database(s) with above steps is not an easy process to perform which involved Data amendment.
Please reconsider your decision to  rename the AuditStore Database before perform above steps.