Yes, but it could be a probe installed on another robot . An example could be a net_connect probe installed on another robot configured to monitor a bunch of servers using ping
When you are monitoring a server using a robot and also using net_connect probe installed on another robot to ping this server , there is a change that it could create another entry and would show up simply as "niscache"
The technical document which I shared earlier helps you identify exactly which probe on the other robot has created this duplicate entry , take a look at the instructions at the second half of the tech doc