There are lots of others in Switzerland
FINA – Swimming – Lausanne, Switzerland.
FIBA – Basketball – Geneva, Switzerland
IFG – Gymnastics – Lausanne, Switzerland
FISA – Rowing – Lausanne, Switzerland
UEFA – Football – Nyon, Switzerland
There are a lot more, I can’t be bothered finding them.
Switzerland has advantages due to tax and banking regulations hence why these organisations, along with huge numbers of private companies, are headquatered there.
I suspect the coruption is incidental to the location and more to do with the amount of money flowing about with very little scrutiny, combined with the influence of sport.
For balance the FIA is in Paris