Mo. Rev. Stat. § 60.130

When it shall appear that the county surveyor is interested in any tract of land the title of which is in dispute before the court, the court shall direct the survey or resurvey to be made by some registered land surveyor, who is a noninterested party, who shall be authorized to administer oaths in the same manner as the county surveyor is directed to do, and shall return such survey or resurvey, on oath or affirmation; and shall receive for his services such reasonable fee as determined by the court.