Hi,
I was doing exploration way before this quest began and when i reached this building i tried moving the shelf and got it stuck on the left side. I kept exploring and doing other trophy related activities and when i finally got to this point in the main story, I’m now unable to advance since it wont let me move the shelf anymore to reach the key behind it. My previous manual save is before even arriving in Paris and I’d like to avoid having to start this dlc all over again.
Hi @leviattann I'm sorry to hear that you are unable to move the shelf in the quest 'Royal Fox Hunt'.
This issue was reported to the development team previously, however they were unable to reproduce it. However, you should still be able to obtain the key that you need.
When you move the shelf you gain access to a room with a window. You then climb out of that window on to a roof and see another window that is boarded up. You can break the boards on the window to access another room which has the key you require. You should be able to access the boarded up window from outside of the tavern. 
Please try this and confirm if you are able to obtain the key and complete the quest.
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