How to Fix Front Facing Camera that Glitches After Replacement?

Hi all,

I am repairing an iPad Pro 12.9" 4th Gen for a customer of mine. She originally needed a screen replacement, (entire LCD was internally shattered, but not the digitizer. ) Now, I am entering week 2 with this tablet after investigating numerous problems that arose since I opened this device.

The client confirmed she had taken this device to only to 1 other repair shop in it's lifetime. This shop had the device for a couple of hourse and returned it to her as 'unfixable'. She ended up choosing my business because, "Don't pick the phony; Better Call Tony!" (Well, actually she chose me due to reviews. But I digress...)

The problem with the 1st shop handling this tablet is that it seems like they broke the front facing camera AND they broke the I/O Cables that house the light sensors and upper mic on the screen.

Now, I discovered the camera was dead after I put on the new display, and I knew that swapping it would kill Face ID, but should still let the camera work as a functional camera in and of itself (selfies, videos, etc.)

After installing a new Pulled-Unit camera from MobileSentrix, I have a non-responsive front camera and nothing but a blurred preview window of the last thing the rear camera sees whenever I tap to swap cameras.

W H A T .

Note, sometimes the camera app glitches, with no camera (front/back) working until I reset the device. I've tried connecting each part of the camera cables one by one to test, and I'm still running up short. (Also, test cameras and front io cables connected, but no success either.)

So, does anybody have an idea as to how I can save this client's front facing camera to at least serve as simply being a camera? (FaceID is dead, and she is ok with it. I already explained it to her in detail about how these repairs kill that feature, typically.)

Thanks for the help and God Bless.

Tony