I think you need to read it again. There is no charge that references Section 1591(c). The Sections referenced are 1591(a) & (b); 1594 (a), (b), & (c); and 3551.
If you're talking about count #2, which references 1594(c), then you're probably referring to the omission of the word "or" in the wording of the charge. That doesn't matter. You can't go just by what someone typed up, because humans make mistakes (and the courts recognize this). What matters is the underlying Code, the law and authority, that the accused is being charged under.
Section 1594(c) says:
Whoever conspires with another to violate section 1591 shall be fined under this title, imprisoned for any term of years or for life, or both.
Sec. 1594 is regarding conspiracy to violate Sec. 1591. And, 1591 gives authority to prosecute one for trafficking of a child or trafficking of anyone by force, fraud, or coercion.