He may have led them TO Little Round Top, but he was met by Joshua Chamberlain’s Maine men in the Devil’s Den, and they never got to the top.
He led them up Little Round Top, never claimed he got to the top. Chamberlain’s Maine men did not fight in the Devil’s Den. The 20th Maine along with the 44th NY, 16th MI and the 83rd PA (Vincent’s Brigade) defended the crest of Little Round Top, against Law’s Alabama Brigade and two Regiments of the Robertson’s Texas Brigade. Shame so many fine soldiers in both armies died for a hill, that some consider, of little value.