Those aren’t NATO forces. Those are local police and UN security. And they had very restrictive ROE. That being said, I think Serbia got screwed in the “partition” deal coming out of the Balkans War of the 1990s, with Kosovo gaining “independence.”
NATO says 25 of their people were hurt Italians and Hungarians and that it is ‘unacceptable” (BBC News)
We don’t care what you think.