(1) The department or self-insurer may require the injured worker or beneficiary to exercise the right of election under this chapter by serving a written demand by registered mail, certified mail, or personal service on the worker or beneficiary.

(2) Unless an election is made within sixty days of the receipt of the demand, and unless an action is instituted or settled within the time granted by the department or self-insurer, the injured worker or beneficiary is deemed to have assigned the action to the department or self-insurer. The department or self-insurer shall allow the worker or beneficiary at least ninety days from the election to institute or settle the action. When a beneficiary is a minor child the demand shall be served upon the legal custodian or guardian of such beneficiary.

(3) If an action which has been filed is not diligently prosecuted, the department or self-insurer may petition the court in which the action is pending for an order assigning the cause of action to the department or self-insurer. Upon a sufficient showing of a lack of diligent prosecution the court in its discretion may issue the order.

(4) If the department or self-insurer has taken an assignment of the third party cause of action under subsection (2) of this section, the injured worker or beneficiary may, at the discretion of the department or self-insurer, exercise a right of reelection and assume the cause of action subject to reimbursement of litigation expenses incurred by the department or self-insurer.