Chosen Solution
After replacing the rear camera I ordered from this site, both cameras aren’t working. The phone doesn’t even recognize that they are there. Before the repair, they both worked but the rear camera shook. The parts are all installed properly and were triple checked.
Sounds like a faulty replacement rear camera, the replacement part is probably causing a short circuit for powering the cameras so it would explain why both won’t work when it’s installed. Contact iFixit support and they should be able to help you out with getting a replacement under warranty.
