However, in subsequent years Rösch suffered a dip in form, which led to him not being selected for the 2010 Winter Olympics. The decline in Rösch's results saw him being dropped by the German Ski Association (DSV) from international competition, both from the World Cup and the second-tier IBU Cup. When his improved performances saw him set to be picked for the 2012 Biathlon World Championships, the DSV did not select him, escalating disputes between himself and the Association and eventually leading him to switch nationalities and apply for Belgian citizenship. However, Rösch's naturalisation was not completed until January 2014, leaving him without enough time to qualify for the 2014 Winter Olympics. During this period, in order to rebuild his sporting career, he resigned from his position in the police force in Germany, and moved back in with his parents.