iCloud Monitoring on macOS for DLP 16.0 RU2 is not enabled. By default the application is added in Global Application Monitoring, however it doesn't monitor.
DLP 16.0 RU2
‘fileproviderd’ application is already added in AFAC, however the checkbox for enabling monitoring is not enabled
To monitor iCloud you need to enable the checkbox manually for ‘fileproviderd’ application in Enforce console under System > Agents > Global Application Monitoring > Search and edit iCloud(Mac) and select the required checkbox as shown below.