If it is blurry without the glass from the rear back cover panel glass then the rear camera needs to be changed as well as the back cover.
Here is guide and parts if you need:
[guide|4890]
[guide|4879]
Replacement rear camera:
[product|IF182-007]
And this is the only back covers they have, honestly I don't know why they don't have a proper one, you can buy one from anywhere online if you need to like eBay:
[product|IF182-021-3]