Post Game Chat Offenses

So I was just recently in a game where a player on our team was not happy about the way I was playing Garen. He/She was relatively polite at first, and obviously annoyed by the end of the game. As soon as we got to the post game lobby screen however, they just went ballistic with all sorts of childish insults.

When I told them I would be reporting them, the response was that the Tribunal doesn't even see post game chat anyway, so they were totally in the clear and I (of course) was dumb for even "threatening" that. I did a quick search online, and couldn't find anything newer than about 2013 on the topic, with pretty much everything saying that it was a planned feature but not currently implemented. Did this ever get around to being put in?

The most awkward part about all of this, was that the PvP.net servers went down before I even clicked the regular report, so I sent this screenshot I had luckily taken a little earlier in the chat with a ticket to support. I don't know if it will do any good but figured I should try. The real reason I'm asking though, is I run into these people all the time. I originally assumed they were just too busy in game with, you know, the game, to bother raging and trolling. Now it suddenly makes sense though, that people are just waiting until they can't get caught to fly off the handle. It's an obvious problem with the system if the moderators really can't see the post game chat, in my opinion, but I guess the ultimate reason I need to know is will I look like I'm the one who's abusing the report system if I say someone was toxic and they never said a single word in the game?