Ways to save people's rank when there is an AFK on the team

I just finished 9 provisional games with all 9 wins. My last game to win and get to my dream league: High silver - Low gold. During champion select we had very good team communication and everyone found a role they wanted. Before the game even started, our mid laner AFK's. Our jungle takes over mid, bot doesn't get any ganks and gets harassed by the enemy jungler. Next thing you know, you have to wait a whole year just to get back to the rank you want because it's almost impossible ranking up.

This issue is really screwed up and it's not fair to people who want to win and achieve a good rank. My best idea for this is to give people a loss prevention if they have an AFK. But has been only AFK from the first 15 minutes of the game. This way your teammate can't leave the game just so you can get a loss prevention. Post your ideas down below.