Are you sure it's only pulling monitored interfaces? I would expect you to get values for all interfaces. Can you show a screen cap of the next step where you test against a node?
EDIT:
oh wow! I get the same result on the Node Details page. I even checked in the CustomPollerStatus table and I only have 3 interfaces being logged, the same 3 that are monitored.
Strange that the customPollerLabels table actually shows labels for all interfaces.