Koll has been working for Zweites Deutsches Fernsehen (ZDF) since 1990. He led the program's London bureau from 1993 to 2001. From 2001 to 2019, he presented political journal Frontal.[2] In addition, he presented the theater magazine Foyer on 3sat from October 2006 to April 2010, alternating with Esther Schweins.[3]
On 1 July 2014, Koll moved to Paris as the studio manager of ZDF.[4] In 2016, was one of the final candidates considered for the leadership of public broadcaster RBB; the position eventually went to Patricia Schlesinger instead.[2] On 1 March 2019, he took over the management of the ZDF capital studio in Berlin, succeeding Bettina Schausten.[5]
Personal life
Koll was in a relationship with Monika Grütters. He is married to Franziska Castell.[6]