(a) A witness shall not receive any witness fees for attendance on a subpoena if such witness is absent from the proceeding, or if the proceeding is continued at any time due to his or her absence, where such absence did not arise from providential cause.
(b) No witness shall receive witness fees from both parties in the same proceeding; the fees of a witness for both parties shall be apportioned equally between the parties unless the costs are all taxed against one party.