There isn’t much on top of the wing that is highly critical. Some planes you can’t even see the top from anywhere in the plane too. An actual issue like leaking fluids or damaged flight control surfaces are visible from the bottom. Something like a few missing fasteners really isn’t t that alarming. I’ve flown plenty of times with some missing, sometimes speed taped and sometimes both the first few times I asked the crew chief but eventually I became familiar with where and how many missing weren’t an issue.