I am afraid that the problem is not connected with the software part or something related. As the webcam is built in the frame of the screen, the problem could be due to a bad part replacement because when you replace the screen, the operating system has nothing to do with it so we can leave this possibility out of the list. The best thing to do right now is to take back the product to the service support because they are the only recommended people to check the status of the webcam. If the problem was somewhat related to drivers or software, then the solution was a click away.
