Since you have your own panel doctors, set up company rules how to deal with their claims and mc but should bear in mind (b) below. Besides panel doctors near the company, you can also appoint more panel doctors in areas nearer to where the staff live.
60F. Sick leave.
(1) An employee shall, after examination at the expense of the employer:
(a) by a registered medical practitioner duly appointed by the employer; or
(b) if no such medical practitioner is appointed or, if having regard to the nature or circumstances of the illness, the services of the medical practitioner so appointed are not obtainable within a reasonable time or distance, by any other registered medical practitioner or by a medical officer;
be entitled to paid sick leave.