I went to the Apple Store last week for the same reason. All they’re going to tell you is they can’t do much and opening the phone will cause even more damage. They ran a couple diagnostic test to check the camera to see if the speck of dust was effecting it and everything came back fine. Yea it’s annoying but don’t try to think about it as much lol.
Damn I guess I should’ve gone to another Apple Store because the employee that was helping me pretty much told me opening the phone will cause more damage.