Never had this problem before. When I began my ranked game, my internet connection is just fine, but for some reason, I couldn't take any actions because of a black screen. I had to dodge.

Same here, a refund would be nice.

bump until Riot responds

Riot doesn't normally refund ELO on individual cases, good luck bro.

I have a stupid idea that may work, it actually doesnt solve your problem at all directly and may seem to mean exactly the opposite at first glance, but whatever:

I have been thinking of a 1 elo gain to each remnant when someone dodges. What do i expect to achieve with this? as all, i do get those black screns and miscellaneous bugs once in a while, and therefor, i lose 10 elo, but i think this sometimes happens to other people as well so they dodge. so, as this happens to many people, not to mention that there are also intentional dodgers, for 1 time u lose 10 elo but that elo goes to the other players, but you will get back that elo when 10 other players dodge. I think its mathematically accurate.

sorry if my english wasnt clear enough, i hope it was understandable.