There can be no contractual obligations regarding what the recipients do with the records. Once they have them, they are free to use them as they see fit - he signed a release for that person.
HOWEVER, you can bet that he would not release them to anyone that he felt he could not absolutely trust to go in the tank for him, or at least to ignore the phrase 'DISCHARGED FOR THE GOOD OF THE NAVY'.
By contractural I mean agreements between Kerry and the recipients as to just what would be done with the records and with if/then clauses at least implied.