I think the "refid" is something used in NTP context which is a property of ntpq/NTP daemon which is a linux based and hence the "ONTAP kernel" commands might not have it which sits above the linux (freebsd).
You could go to systemshell (freebsd linux), where you could locate the linux based 'ntpq' utility that might fetch you the refid:
Example: Log in to the system shell for a node. ::> set -privilege diagnostic ::*> system node systemshell -node node1 node1% sudo ntpq -pn
Note: You use the hidden ' diag' account to log in to system shell. This user needs to be unlocked and the password has to be set, if never configured.