Evading LeaverBuster and Int'ing Check

Recently, I've run into a recurring problem of players who either intentionally feed or ragequit, but they game the automatic checks in such a way as to avoid being punished. In both cases, the behavior was deliberate and malicious, but as of yet (a few days after these incidents), they have not been punished.

Incident #1: eight seconds into the match, with absolutely no provocation in champion select, our ADC types "open mid", runs down mid lane, and parks herself ~200 units outside of the enemy turret range, letting herself get killed. Then, she runs down bot lane for the rest of the match, garnering 14 deaths in 20 minutes. I suspect she is a smurf who was trying to deflate her ranking, because she was very careful to hit the sort of benchmarks that Riot looks at to determine whether or not the player is supposedly trying (for instance, building normally, even getting a solokill), while nevertheless utterly screwing over her team. Altogether, she ended the match 1/14/0, and her only messages in chat were "open mid" and "fuk".

Incident #2: our support was raging at our ADC and jungler, insisting the game was over even though we had a one-dragon advantage over the enemy team and were within a few kills and two turrets of them. After initiating a surrender vote at 20 minutes (and failing by a majority) and raging some more, she disconnects. We keep on playing, because we really weren't that far behind. Several minutes later, the player reconnects just long enough to initiate a surrender vote (once again failing), rage at us yet some more, and then disconnects again. This occurs twice more before we finally lose the game.

It's absolutely sickening that players get away with this sort of thing. In both cases, it was clear to players on both teams that the behavior I described here was intentional, and I'm sure that, in both cases, they received multiple reports from each team. Despite this, they do not appear to have been reprimanded at all.

EDIT: I'd be happy to add the matches if anyone would like verification, but I'm not sure if that violates Riot's policy against singling players out/pubic shaming.