If that's the case, then they really haven't anything.
They have potentially fouled up regarding the rape case and if he walks on a technicality, then they have no reason to hold him in detention beyond his drug sentence unless they can nail him for something else in the meantime.
As an aside, if he walks on the rape conviction on a technicality, can he be tried again anywhere for the same crime, or would that also run foul of human rights ?
So he has an appeal pending re: The validity of his extradition for a different crime. Both countries involved can liaise and add crimes to warrants apparently, but I doubt they can do it until this latest appeal comes to fruition - which could be next month.
Even if it's overturned he will probably still be held, as a retrial may ensue and he is an obvious flight risk.
The main issue for me seems to be if it can be argued that he will get a fair trial, now that his ugly grid has appeared in every newspaper and internet portal on the planet. Now he has defence lawyers clamouring for his attention, he's bound to get top class representation - pro bono too no doubt.