Any state party to this compact may accept federal aid for use in connection with any facility or program, the use of which is or may be affected by this compact or any contract pursuant thereto and any patient in a receiving state pursuant to this compact may participate in any such federally aided program or activity for which the sending and receiving states have made contractual provision; provided that, if such program or activity is not part of the customary regimen of the facility or program, the express consent of the appropriate official of the sending state shall be required therefor.   [PL 1979, c. 303 (NEW).]