Last datadisc does not exist?

I've combed through the Koboh map probably 5 times searching for the missing datadisc. All map upgrades found, all exploration at 100%, all databank entries at 100%, all holotactics completed, all bounties completed. Marker for the last datadisc does not exist on the map. Forever stuck at 99% complete. The datadisc seems to not exist. Not sure what to do.