I did the crypts in this order and had my achievements snapped in case it wasn't counting. Here is the order I did them in
Soviet Installation Vista Camp, Hidden Refugee Base Camp, Ridgeline Camp, Ruins Encampment, Lost City
Ruins encampment is the one that glitched for me! I'm not sure if this is the same for everyone but for me it was this one! Enter the crypts and when you get to the chest don't open it! what you want to do is create a backup save by going in the pause menu and go to " change save slot" change it to slot 2 or 3 and then change it back to 1, that way if a crypt glitches you can reload your backup and overwrite your "glitched save"
When I had ruins encampment glitch on me I was at 40% I collected the treasure and it didn't go to 60% it just stayed at 40% I loaded my backup save and then I went to the Ridgeline camp crypt and my tracker went to 60% after collecting that crypt treasure. I then went back to the ruins encampment crypt and was able to get it to register and go to 80% ( I'm guessing this needs to be done in a specific order but who knows) and finally when I went to the lost city it popped as soon as I opened the last crypt chest. I cannot guarantee this is the same case for everyone but it worked for me, really frustrating since there is no consistency with this achievement.
Remember always make a backup before you collect any crypt treasure, if a crypt glitches and you don't have a backup save it won't count on the achievement tracker and you'll be screwed and will have to do another Playthrough, I hope this helps you guys out and hopefully you don't come across the above problems
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