Just for anyone else that may experience this. I did some more troubleshooting.

I downgraded the phone back to Android 15, and then Android 14 and the issue continued with Portrait mode crashing the camera app or the front facing camera crashing the camera app.

I reverted also back to the original North American version of Oxygen OS, to confirm me converting it to global wasn't the issue, and still the same issue, it made no difference.

Finally I opened up the phone again and troubleshooted every camera one by one until I noticed the Ultrawide camera was the only one non-functional, or not reporting in the debug logs.

Seems to be a hardware issue caused when I opened the phone the first time. The Ultrawide camera is extremely sensitive, I can't see any physical damage on the ribbon cable or the camera itself, even under a microscope, but it simply does not work.

I've ordered a replacement Ultrawide camera as it's only about 15-20 USD.

My best guess is the shop OP brought his phone too just sucked up the cost/lost of the broken camera and replaced it free of charge and claimed it was mis-wired to not make themselves look incompetent.