Just finished the last questline in Southern Dreadlands, went to claim my trophies and found that the one completing that last questline is overlapped by the one for completing all of the zones’ questlines, so it can NOT be clicked on to get the points or clear it from the codex.
https://i.imgur.com/5Ej3Bbp.jpeg
SOLVED: After achieving some other trophies from the same “General” category, the “button” to retrieve the “Southern Dreadlands” questline one became available to be clicked.