Knight's Cross was made by Oberst Hannes Trautloft, at the time Inspekteur der Tagjäger (Inspector of Day Fighters), at Fürstenau airfield on 5 December. Following the presentation, Borris led a flight of five Fw 190s against a formation of B-17s bombing Berlin and managed to shoot down a straggler from the 452d Bombardment Group west of Lingen. At Fürstenau airfield, the Gruppe was equipped with the Fw 190 D-9 aircraft and flew twelve combat missions in support of the Ardennes Counteroffensive, also known as the Battle of the Bulge. In these missions, Borris lost eight pilots killed in action, five were wounded and further four pilots were taken prisoner of war (POW). On 31 December, 20 Fw 190 aircraft from III. Gruppe of Jagdgeschwader 54 (JG 54—54th Fighter Wing) under the command of Oberleutnant Hans Dortenmann arrived at Fürstenau in preparation for Operation Bodenplatte. Bodenplatte was an attempt at gaining air superiority during the stagnant stage of the Battle of the Bulge. That evening, Borris briefs the pilots of the mission, which is the Grimbergen Airfield. Led by Priller and Borris, 47 aircraft from the Geschwaderstab and I. Gruppe, and further 17 aircraft from III. Gruppe of JG 54 took off at 08:14 on 1 January 1945. Flying at an altitude of approximately , the attack force sustained losses during the approach to the target area, largely due to anti-artillery fire. The airfield at Gimbergen was almost completely abandoned, the damage inflicted was minimal, and the losses sustained where significant. III. Gruppe of JG 54 suffered five pilots killed or missing in action, plus four further taken prisoner of war, Borris lost six pilots either killed or missing in action, making the mission a total failure. Borris claimed his 43rd and last aerial victory on 14 January and German forces were on the retreat in the Ardennes. At 15:25, Borris led a flight of 31 Fw 190 D-9s from Fürstenfeld, three Fw 190 had to abord the mission prematurely, on mission to protect the German jet bomber airfields in the vicinity of Rheine-Hopsten. Borris and his flight of 28 aircraft encountered Spitfires of the Second Tactical Air Force with the two Norwegian squadrons No. 331 and No. 332 Squadron. In this encounter, Borris claimed a Spitife shot down at 15:45 in the vicinity of Ibbenbüren. Based at Flensburg Airfield, Borris surrendered I. Gruppe to British forces on 6 May 1945.