As additional compensation to a state employee, a state agency may pay or reimburse the employee for a travel expense the employee incurs while obtaining medical care for the employee if:
(1) the expense is incurred outside the employee's designated headquarters;
(2) the purpose of the employee traveling outside the employee's designated headquarters was to conduct official state business;
(3) waiting to receive the care until the employee returns to the employee's designated headquarters would be unreasonable; and
(4) the expense is paid or reimbursed only to the extent it would have been paid or reimbursed had it been incurred while conducting official state business.