What is your OCUM version? The thing is currently no OC Unified Version ( 5.x or 6.0 ) monitors and stores this "comment" field for the vservers and WFA acquires Data from what is seen by OCUM. Hence this field is currently set to Null by WFA.
Perhaps in future if OCUM starts to monitor/store this "comment" information of the vservers, WFA cache queries maybe will get modified to acquire it.
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