Madeleine was Abducted. I just don't know for why or by whom. But someone took a huge risk. Or they would have done if it hadn't happened in Portugal, where they seem to be much more interested in fitting up Mothers.
I don't know if Brueckner was involved with this or even if he was alone, albeit doubtful if it was him.
Even from the little we know it is obvious that the phone data the Policia Juducairia had to hand in 2007 justified that certain criminals had questions to answer when the trail was still fresh.
I don't think it is benefit of hindsight that led Operation Grange to play 'catch up' six years down the line when that diligence was carried out and eliminated three burglars from the inquiry. It was as the result of good police work using the information they knew had to be checked.
To date the Germans haven't come up with anything which eliminates Brueckner as they are obliged to do if they find it. But similarly 'proving' his guilt beyond reasonable doubt will be a Herculean task. So the ball is in his court when the presumption of innocence is considered.
It all goes back to the original police incompetence which led to Justice being compromised and McCann presumption of innocence being trampled into the Portuguese dust.