At the Second Battle of El Alamein, during the period of 23–31 October 1942, Kibby distinguished himself through his skill in leading his platoon, after its commander had been killed, during the first attack at Miteiriya Ridge. On 23 October, he charged a machine gun position, firing at it with his Thompson submachine gun; Kibby killed three enemy soldiers, captured 12 others and took the position. His company commander intended to recommend him for the Distinguished Conduct Medal after this action, but was killed. During the following days, Kibby moved among his men directing fire and cheering them on. He mended his platoon's telephone line several times under intense fire. During 30–31 October, the platoon came under heavy machine gun and mortar fire. Most of the members of the platoon were killed or wounded, and by the time the battle was over the total fighting strength of the battalion was down to 213 men from an establishment strength of 910. At one point before midnight on 31 October, in order to achieve his company's objective, Kibby moved forward alone, to within a few metres of the enemy, throwing grenades. Just as his success in this endeavour appeared decisive, he was killed. By the morning, the 2/48th consisted of fewer than 50 unwounded men. The posts captured by the 2/48th that night were lost to the enemy, who buried Kibby with other casualties in a common grave. Later, when the area was retaken by Australian troops, the men of his unit searched for ten days, found the grave and reburied the men individually.
Kibby was subsequently recommended for the posthumous award of the Victoria Cross, the highest award for gallantry in the face of the enemy that could be awarded to an Australian armed forces member at the time. The citation was partly based on a note found in the pocket of his dead company commander. The award was listed in the London Gazette on 26 January 1943, and the citation read:
During the initial attack at Miteiriya Ridge on the 23rd October, 1942, the Commander of No. 17 Platoon, to which Sergeant Kibby belonged, was killed. No sooner had Sergeant Kibby assumed command, than his Platoon was ordered to attack strong enemy positions holding up the advance of his Company. Sergeant Kibby immediately realised the necessity for quick decisive action, and without thought for his personal safety he dashed forward towards the enemy posts firing his Tommy-gun. This rapid and courageous individual action resulted in the complete silencing of the enemy fire, by the killing of three of the enemy and the capture of twelve others. With these posts silenced, his Company was then able to continue the advance.
After the capture of TRIG 29 on the 26th October, intense enemy artillery concentrations were directed on the battalion area, which were invariably followed with counter-attacks by tanks and infantry. Throughout the attack that culminated in the capture of TRIG 29 and the re-organisation period which followed, Sergeant Kibby moved from section to section personally directing their fire and cheering the men, despite the fact that the Platoon throughout was suffering heavy casualties. Several times, when under intense machine-gun fire, he went out and mended the platoon line communications, thus allowing mortar concentrations to be directed effectively against the attacks on his Company's front. His whole demeanour during this difficult phase in the operations was an inspiration to his Platoon.
On the night of 30th–31st October when the Battalion attacked "ring contour" 25 behind the enemy lines, it was necessary for No. 17 Platoon to move through the most withering enemy machine-gun fire in order to reach its objective. These conditions did not deter Sergeant Kibby from pressing forward right to the objective, despite his platoon being mown down by machine-gun fire from point-blank range. One pocket of resistance still remained and Sergeant Kibby went forward alone throwing grenades to destroy the enemy now only a few yards distant. Just as success appeared certain, he was killed by a burst of machine-gun fire. Such outstanding courage, tenacity of purpose and devotion to duty was entirely responsible for the successful capture of the Company's objective. His work was an inspiration to all and he left behind an example and the memory of a soldier who fearlessly and unselfishly fought to the end to carry out his duty.
— The London Gazette 26 January 1943