If you want to trigger VNC viewer from a BatchPatch row you would need to create a local command with the VNC viewer command line command for your viewer. For example RealVNC the command is: vncviewer.exe <computer>. In a BatchPatch local command you can use $computer for BatchPatch to insert the host name for the row into the command line. So your local command would be:
vncviewer.exe $computer
or if you need to specify the full path to the viewer then do:
C:pathToViewervncviewer.exe $computer
This link explains how to create commands in BatchPatch:
How to Hard-Code Your Own Custom Commands in the BatchPatch Actions Menu