I don't know what log you are looking at. People should completely avoid looking at any macOS logs since they are no longer useful for troubleshooting. Plus they contain a lot of scary sounding items that are completely innocent and they contain a lot of nonsense junk. The only useful logs are the Kernel Panic logs if you know how to interpret them.
As for PhotoBooth being used, that would not surprise me since I use PhotoBooth to test the camera after a repair.
What is more concerning is you gave your password to someone. Apple no longer asks for a user's password due to all of the privacy & security concerns. Even an AASP is not supposed to ask for your password anymore. Apple's current rules are if a tech needs access to your user account to fix a software issue or to gather more details, then they are supposed to have you enter the password to unlock the system, then stand there watching what the tech is doing so that you know the tech is not doing anything nefarious.