You can look at statistics though, right? Trying to determine inting off one game is definitely tough, but if someone's average performance is, for example, fewer than 2 kills/assists and more than 8 deaths in their last say, 10 games, and gotten a CS score lower than 40 and contributed to less than 10% of their team's objective dmg, then we can probably say they've been inting, right?

These are stats we get at the end of every game, so they must be tracked somewhere. This is one or two SQL queries (avg objective dmg might be its own query). Obviously we can tune these numbers until they make sense, but just throwing your hands up and going "it's difficult" won't solve any problems.