This is misleading. I was NOT in a pre-made group and got these messages on two different occasions.
"You are now back in a chat room with just your premade."
"Rakvir did not accept the AFK check. Your group was removed from matchmaking."
I did not join the queue with anyone so why would it even say this? I WAS getting grouped with with mostly the same bunch of people, no matter how many times someone dodged, however. So, basically, if that was it, then that raises even FURTHER issues. Why are we pre-set to always be grouped with the same people? This gives less incentive to keep queued if someone doesn't like even ONE other person if they know that they WILL be grouped again with them instead of chalking it up to bad luck.
Also, the second notice just feels bad. I was not AFK. I purposely chose to click to not accept when I realized I was only getting grouped with the same people as I had been before, including a troll jungle I had previously played a game with, despite having waited a solid 8 minutes before queuing up again.
AFK means 'away from keyboard'. Why is clicking to deny the match-up giving the same message as if I actually was not present?