Hello,
I am sure these featues work on SEP 11.x all client versions.
Allows the users to pause or snooze the scans that start on their computers.
This option is available when you select either Show scan progress or Show scan progress if risk detected. This option is enabled by default. When this option is enabled, click Pause Options to specify pause and snooze options.
Could you check if these client machines are on the same Version and on the same system timing as of scheduled scan??
I agree that in case if you are taking a RDP session on the machine, you may not see the Scan Pause Option.
However the same can be seen on local machine by the Local user who is logged into the machine.