From my understanding Kabuto uses a service that turns on when the computer boots up. This updates the clients Kabuto app and also reports to the Kabuto Dashboard that the computer is turned on. Although if the customer has really bad internet I have noticed that Kabuto does not report accurately which is expected. I mean a > 1200 ms ping time is not good at all and would cause anything that uses the internet to not report accurately.
It also could be that the clients lack of "internet" is causing Kabuto not to update correctly like it should and you could be running an older version of Kabuto on the clients computer. In these scenarios it is best to just uninstall Kabuto and reinstall it on the clients computer. In my experience this usually is the quickest and best way to repair a corrupted out of date Kabuto installation.
I hope this helps you out.