So, lets say that some player queue up to the random heroic dungeon to get his daily Emblem of Frost. Since it is "random", he get into an Occulus group.

Now we all know that everybody (no exception) hates Occulus. How will Blizzard prevent that this player just get out of the group and queue up again to get into a more fun dungeon, like Utgarde Keep or Nexxus?

I don't think that a "deserter debuff" would fix that. I'm sure that I speak for everyone here when I say that I rather sit out of the dungeon queue for minutes or even hours just to avoid a lame Occulus run, especially with PuGs.