If you have the map (meaning both halfs of it) you have to burn the hay in the tent. then you can enter

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I have both fragments, but they don’t combine together? What do I do?!

If you missing one of the fragments. it's probably the udnerground one since there are two camps close to each other with a bag and a book hanging around just check if you are at the exact reight location. took me some time to realize.

I entered but didn't get the achievement, what else I have to do?

The entrance is under the chest that you collect, under the hay.

In Location 1 The Hoarders' Treasure Map did not spawn after finishing the required quest. What do I do?

You guys need to burn hay on the ground inside the tent, you can use elemental sight to see what you need to burn. Might not show up if you collected the maps in coop mode; just relog to fix it

i collected 2 of the fragments but the entrance didnt show up
what did i do wrong??