@milinaphalke You can write a script to check the status of your identityrequest and if it is completed, then only move to end step. otherwise, you can move the workflow to wait state and again recheck the status.
If you want the workflow to halt until the access request completes, you can add a wait loop to continually check the status and after its “Complete”, do your custom audit
We also have a similar requirement. We check the status of provisioning result to write the audit event. Access request status is updated after “Perform Maintenance” and “Perform Identity Request Maintenance” task run.