ANYBODY can get in that instance, what you do is you go to the top right of it, where it has a space between the jagged teeth looking rocks, then delete your hearthstone, click on the big ? on your toolbar, click issues that GM's can assist with, click stuck, then click auto-unstuck, then when the auto-unstuck bar finishes you will be on the other side. And for those of you who are scared of deleting your hearth, talk to an inn keeper and say i want to bind myself to this inn, and you get another free hearth.