I have not been in there personally but 2 things:
The capsule you're trying to craft already exists as an item in the map, if you have not destroyed it (you would know... trust me) or sold it, you do not need to make one, snoop around more.
If you mean you are stuck and can't climb out after, you can climb by holding a hook and using it (it throws the hook and you can then scroll to change it's length)
If you craft a hook you get 2 half hooks, which are more useful for climbing as you won't accidently link it to walls and such, but that means it becomes useless for attaching stuff together