As per JAYP's guide, remember that in the NODE LINKS,
"....Matters are complicated slightly by a quirk in the mission builder. Although the debrief variable you just selected is designated as 'debrief variable 1' when you select it from the drop-box in the link-modify window, when you look at the condition in the node-information window, it is reported as 'debrief variable 0' "
Maybe the 0's and 1's got confused in the link modification???