These are two different events. The event you mention took place in late August against the 8th Panzer Division. The KV-2 event occurred earlier, in late June, during the 2nd day of Barbarossa against the 6th Panzer Division. With Don's mention of 88s failing to initially take out the tank and that it was ultimately knocked out in the end, he most likely is referring to the KV-2 event which is mentioned on the second link you posted under "The monster at the road".

Kolobanov probably destroyed more tanks during his engagement, but the KV-2 held up its opponents for a longer amount of time with apparently no help from any other Russian tanks.