I could try to create a duplicate map and edit entry and exists but... wellll. I'm okay with editors and great with patience, but I'm lightyears away from people who can actually script and code.
edit: okay, the way I see it, there are two actual problems. One would be to duplicate the map file inside the lgp, compile it again and then change the map ID so you can have an existing field connect to it. The second is to make a 'new' exit in an existing map to said field.
Alternatively, you can clone the ancient forest and have the sleeping forest connect to it and then the cloned ancient forest connect to coral valley.