Secondary Controller is back in service after a call to TAC. The proper way to place the controller back into a Master/Standby is as you suggested. The steps we took were as follows.
Run through the intial configuration of the Controller to set up the basic settings. Once that is complete, load the Controller specific information such as Interface configurations, VLANs, Certificates, User accounts.
Configure VRRP settings and join the new Standby back to the HA Group. Once complete, wait for synchronization to occur between the 2 controllers. Verify configuration and make sure nothing is awry or missing from the new Standby.