(a) If the parents agree to one or more provisions of a parenting plan, the court shall so order, unless it makes specific findings that:
(1) The agreement is not knowing or voluntary; or
(2) The plan would be harmful to the child.
(b) The court, at its discretion and on any basis it deems sufficient, may conduct an evidentiary hearing to determine whether there is a factual basis for a finding under subdivision (1) or (2), subsection (a) of this section. When there is credible information that child abuse as defined by section 49-1-3 of this code or domestic violence as defined by section 27-202 of this code has occurred, a hearing is mandatory and if the court determines that abuse has occurred, appropriate protective measures shall be ordered.
(c) If an agreement, in whole or in part, is not accepted by the court under the standards set forth in subsection (a) of this section, the court shall allow the parents the opportunity to negotiate another agreement.