(a) Subject to the assessment of costs under Subchapter G, the cost of initial genetic testing must be advanced:
(1) by a support enforcement agency, if the agency is providing services in the proceeding;
(2) by the individual who made the request;
(3) as agreed by the parties; or
(4) as ordered by the court.
(b) In cases in which the cost of genetic testing is advanced by the support enforcement agency, the agency may seek reimbursement from a man who is rebuttably identified as the father.