Hmmm i'd find it strange if they banned people simply for using Oque. I'm sure i've seen blue posts in reply to people who have complained about not being able to find groups for stuff on an under populated realm where a blizzard blue poster has actually recommended the Oque addon as a solution... The addon has also been recommended on popular and reputable websites such as wowinsider.
I normally use Oque to find my ordos and Celestial weekly kill on my main and a few alts. I enable it, find my groups for that on a wednesday and then turn it off.. I wasn't aware that it kept you logged in when afk and it's never come up because I disable it whenever i'm not actively using it.
I've heard the reason that OQ has been removed from websites such as curse is simply because it asks for donations on it's in game interface... Nothing to do with the functionality of the addon being against any rules.
I'd like to see a blue post on the subject... Blizz know it's a popular addon that thousands of players use so I find it hard to believe that they'd start banning players who would clearly have no reason to believe they were doing anything wrong.