(2) Subject to the provisions of subsection (1), where an unconditional offer in writing of any amount as compensation has been made to any claimant by or on behalf of the authorised officer and the sum awarded as compensation does not exceed the amount offered, the chairperson shall, unless for special reasons he or she thinks it proper not to do so, order the claimant to bear his or her own costs and to pay the costs of the authorised officer so far as the costs of the authorised officer were incurred after the offer was made; and, where the claimant has failed to put forward a proper claim in sufficient time to enable the authorised officer to make a proper offer, the foregoing provisions of this section shall apply as if an unconditional offer had been made by or on behalf of the authorised officer at the time when, in the opinion of the Board, a proper claim should have been put forward and the claimant had been awarded a sum not exceeding the amount of such offer.