Balancedness of Normal Bundles of Rational Curves in Grassmannians

In projective space ${\mathbb{P}}^r$, the normal bundle of a general rational curve of any degree $d\ge r$ is balanced except over fields of characteristic 2. In arXiv:2404.08102, Coskun, Larson, and Vogt found counterexamples to the naive generalization of this statement to general rational curves in Grassmannians and proposed a conjecture for when the normal bundle is balanced. In this paper, we prove their conjecture for the Grassmannians $G(2,4)$, $G(2,5)$, and $G(2,6)$.