Mo. Rev. Stat. § 545.070: Names of witnesses must be affixed to indictment.

When an indictment is found by the grand jury, the names of all the material witnesses must be affixed to the indictment; other witnesses may be subpoenaed or sworn by the state, but no continuance shall be granted to the state on account of the absence of any witness whose name is not affixed to the indictment, unless upon the affidavit of the prosecuting attorney showing good cause for such continuance.