The Last Tiger Skin Bug

Well, I've tried it all. Troubleshoots, manual fixes, support tickets. But still to no avail. I've completed all challenges and collected all the letters, but as shown in the image linked, it says I have none unlocked at the bottom, but it says I have them all on the side. This bug is driving me nuts. I hope to find a solution somewhere in here, or at least get the issue recognised better. I've tried the usual fix of deleting the save, re-doing the mission and putting the 'settings' folder back in the system. Any help is greatly appreciated folks.