Sweden is just a front for law enforcement in the USA. The entire goal of this disgusting show is to get him on US soil where he will be "disappeared". They can't directly ship him to Gitmo and start the water boarding, but they can do the equivalent without leaving the continental USA.
It will go something like this. First, they will try and stall for a few days and pretend he is still in Swedish custody. In fact, he will already be buried in some black facility in the US. Then, after he can't be found the US will deny that they have him. That will make it much more difficult for his lawyers to force the courts to grant him his basic rights, like the right to an attorney.
This could literally drag on for years. Given that the security courts have, as far as anyone knows, never stopped the authorities from doing whatever the hell they want, it will be like he dropped off the face of the earth.
Meanwhile, he will be tortured. It will be somewhat less physical then Gitmo because they will at some point need to show that he is still breathing and can say a sentence with words of no more then two syllables. But as far as destroying him mentally, they will do whatever they think they can get away with.
The goal is not to find out about the leaks, the goal is to make an example and act out their rage. Make no doubt, these people are perverts in a sexual sense. They derive very intense personal pleasure from the destruction of their enemies. They're seriously deranged.
If he is never seen again then it will be because someone got carried away and killed him. That would not be their plan, but we all know how that actually works out. How many innocent people did they kill looking for Bin Laden? They have admitted less then ten so far, but it seems likely it was in the hundreds or even thousands. Seriously, they killed one person because he was tall and had a beard and was somewhere that was a possible Bin Laden hideout (i.e. somewhere in Iraq or Pakistan or Syria or Lebanon or
So back to the question: how long will it take for him to be "extraordinarily rendered" to the US? There should be a betting pool. A good bet would be that he doesn't even sleep in Sweden. That would leave the smallest footprint for a cover up.
Of course, the real problem with running that pool is that it could take decades to determine the winners. Or there will never be a winner. In some sense a complete disappearance makes it easy, because they want him to be forgotten. That would be a real victory in their eyes.