Cika wannan jumla: Siegenthaler ya yi gasa tare da Team Switzerland a gasar cin kofin duniya ta 2013,
2014 da 2015 IIHF Gasar Cin Kofin Duniya ta U18. An san wasan nasa na ban mamaki lokacin da aka sanya shi a cikin 2015 U18 WJC All-Star Team. An kuma zaɓe shi don shiga gasar tunawa da Ivan Hlinka a shekarar 2014.