Yeah, the map is a tad confusing, but you've got it. You can access area 2 from area 3: Just above the table, the ceiling is open to the loft area. When run it, jumping up from the table and climbing up works. I also describe the descent from area 1 to 3 as feeling extra long, like you're going down two storeys.
I hope running it goes well! Let me know if you have other questions.