Rear camera is blurry after housing

The FaceID is located within the front camera/speaker assembly so shouldn’t be affected by rear camera replacement. As for the camera itself, unfortunately, it does seem to maybe have sustained some damage during the repair to the autofocus module, although I’d suggest completely wiping the device to ensure no software issue is causing this (if the device belongs to a customer and you aren’t able to do this, try moving the camera into another compatible device that can be reset and tested), and if the problem persists after this, replace the rear camera entirely.