As soon as practicable after August 10, 1988, the Secretary shall offer to undertake negotiations with the Association, leading to the execution of an agreement with the Association to serve as Administrator under this subchapter. The Secretary may appoint the Association as Administrator if such agreement is reached within 90 days after August 10, 1988. If no such agreement is reached within such period, the Secretary shall appoint another person as Administrator under this subchapter, after consultation with leaders of affected Aleut villages and the Corporation.