The degree of the hypersurface of pfaffian cubic fourfolds

According to Example 3, p. 319 of

Li, Zhiyuan; Zhang, Letao: Modular forms and special cubic fourfolds, Adv. Math. 245, 315-326 (2013). ZBL1290.11077,

the degree of $\mathcal{C}_{14}$ should be 915678.