He served as a secretary in the Politische Abteilung at Auschwitz concentration camp beginning in June 1940, where he participated in mass murders using the Genickschuss method of firing one bullet into the back of the neck, established by SS-Untersturmführer Maximilian Grabner.
[2] Quakernack worked as a team leader in the crematorium at Auschwitz and participated in the gassing of Soviet POWs at the end of 1941.
[4] During his time in Auschwitz, he was known to personally kill prisoners by having them led to a big warehouse, which Quackernack would then also enter under the influence of alcohol.
Former member of a Sonderkommando unit, who were tasked with removing the bodies on trucks and taking them to the crematorium, recalled that Quackernack stood in the middle of the warehouse, surrounded by dead bodies, holding a smoking gun, with his uniform entirely red from blood and laughing loudly.
On 23 January 1945 he accompanied a death march of 500 prisoners from Auschwitz to the Hanover-Mühlenberg concentration camp [de] arriving around 3 February 1945.