If there is an AFK for a decent portion of the game in Solo/Duo Queue, the others do not lose LP.

By decent I mean they were afk for at least 7+ minutes before the game ended where they just never came back. The solo players should not lose the LP in those games since it was not their fault and there was nothing they could do about it. The AFK's duo (if they have one) would lose LP still. However, that afk player would get a more intense punishment, like a 3+ hour ban or something.