(a) If application is made to the Commission within 15 days from the date when notice of the award shall have been given, the full Commission shall review the award, and, if good ground be shown therefor, reconsider the evidence, receive further evidence, rehear the parties or their representatives, and, if proper, amend the award: Provided, however, when application is made for review of an award, and such an award has been heard and determined by a commissioner of the North Carolina Industrial Commission, the commissioner who heard and determined the dispute in the first instance, as specified by G.S. 97-84, shall be disqualified from sitting with the full Commission on the review of such award, and the chairman of the Industrial Commission shall designate a deputy commissioner to take such commissioner's place in the review of the particular award. The deputy commissioner so designated, along with the two other commissioners, shall compose the full Commission upon review. Provided further, the chairman of the Industrial Commission shall have the authority to designate a deputy commissioner to take the place of a commissioner on the review of any case, in which event the deputy commissioner so designated shall have the same authority and duty as does the commissioner whose place he occupies on such review.