You sound like this swain i was with...... They were mid and we had a lulu top. Lulu made the illaoi 0/4. Swain gave yasuo first blood, but with ganks, got yasuo to 3/5. The illaoi and yasuo switched. Illaoi beat swain np, lulu couldnt deal with the yasuo. Swain was saying the lulu was worthless and needed to get armor, but swain didnt have armor either. Then was saying this isnt season 5 lulu top is useless..... Complain complain complain.
All in all, dont rage, makes you look like a jerk. The karma d/cing should be reported. Karma top works when played well, kata top which you do not see hardly ever..... So idk how you can claim that you knew it was going to be kata top (karma into kata top remark you made).... And the kata probably outplayed the karma. Deal with it. It happens. You get outplayed im sure as well. You lose lane. You die many times. It happens. Thats league. Do not try being a jerk on forums complaining about karma top when you obviously are not even trying to thibk about what you are saying before you say it.
Yes, karma was in the wrong for d/c. Report her for that. Everything else of your arguement is silly unless it was an intentional feed, which unless you were paying more attention to top than you were in bott (which gets you killed and turn you into a feeder) you do not know if it was intentional unless they run under enemy tower 24/7