Without the file from his PC (not from another machine) it is all speculation, but anyone can try the following:
Change any executable to the untrusted group and you will see that it will be blocked in the webcam protection module ...
View attachment 211210
View attachment 211211
All I can say is that oversee.exe isnt trying to access the webcam, to say otherwise is a lack of knowledge of how Kaspersky works.
Maybe he is using a cracked/illegal version (notice the lack of the icon) that made the digital signature invalid, it can be a lot of things and like I said, without the file it is all speculation.
Being inquisite is nice, but spreading FUD is not.
Point is: Avast isnt trying to access your webcam.