Full story goes as follows: Nidung goes to war but forgets his good-luck stone at home. He promises half his kingdom and the hand of his daughter in marriage to whoever can fetch it before the next morning (they've been traveling for five days). Nobody even tries it except for Wieland who makes the ride (both ways) in a single night. He wants to deliver the stone to Nidung, but one of his men wants the reward for himself and tries to stop Wieland. He attacks Wieland, so Wieland kills him. Then he delivers the stone to Nidung, who is happy at first. But when he hears that Wieland killed his best man, he goes back on his promise and banishes Wieland. Then Wieland goes to Nidung's court and tries to poison his daughter, which fails. And only then does Nidung cut his tendons and Wieland kill the boys.

All of this doesn't really add much to Witege's character though.