iPhone 13 Pro Max 256 gb Sierra Blue says camera is not a genuine part

I have only had my phone for 6 months and suddenly in December, the phone started saying one of the parts is not genuine. I have applecare plus and this phone has never been opened or operated on. I took it to an apple store where it failed multiple camera tests. THEN APPLE TRIED TO CHARGE ME $1400 FOR A NEW DEVICE!!! They are saying that the repair facility discovered a non-genuine apple part, which is impossible. They clearly ran a test on the phone and the phone said there was a non-genuine part, just like the message on my phone. I had to spend 3 hours total on the phone with apple support to convince them to escalate the issue and I have now been 5 days without a device. They are saying that they need an engineer to look at the actual phone and we can go from there. I see a lot of people on here with various iPhone 13 models and people on here are saying to just bring it to apple and it's a simple fix. This issue is not. I had to be very stern with everyone on the phone and switched service reps 3 times just to get them to offer to investigate further and not just offer a $1400 replacement or my broken phone back.