He does not, as I said in Germany you can`t have double citizenship. I met this guy at ANAC. He told me that the first time he got his CCF there was a bunch of Bolivian PLAs taking the test, he had no idea of the reason.
You might want to check
German nationality law - Wikipedia, the free encyclopedia before you make absolute statements. He could easily maintain his citizenship by birth (Brazilian) and citizenship by family (German).
One of my buddies when I use to work for Flight Safety International was a guy from Peru that flew in Brazil.....even for FAB.
Exchange service is quite common in the military world, during my military career I served with the Air Force of another country.
Marica Taxi aereo has an English pilot, he has been flying in Brazil for one year now.
Maybe he was born here too? Maybe they need his experience for oilfield or fire-fighting work? Maybe he works for charity?
TTFN