Can't get out of Gray Garrison

I have been unable to get out of the Gray Garrison for a month. I have killed and explored all 3 levels and it still states I can’t leave until I complete the Gray Garrison. How do I complete it and move on. Very frustrated and a newby. Please help?

Have you interacted with the Wardstone on the third level yet?

If you have already defeated the last boss and did what is needed to the wardstone and it is not letting you leave. Load the toybox mod and use the Teleport to map function. Don’t know if it won’t break your game, but I used that mod to get out of the ivory prison when I was stuck in it.

I can’t get access to the third floor. I have killed everything on both the 1st and 2nd floors but cant proceed. Any idea?

Where exactly are you stuck? Do you know where the exit should be to the 3rd floor?

Map of Gray Garrison, Level 2 with directions to stairs going up to the third floor: