It is seriously laughable that Pakistan proposed UN Probe when they themselves dont believe in UN, NATO and other agencies. Even UN will probe and provide the proof to Pak that it is there army who did it then they will again go back in Denial mode stating that it is India-US-Israel nexus. We saw what happened when third party FBI has captured Headly and he informed everyone about involvement of Pakistan "State factors" in it. Dossiers may contain Interpol documents for Hafiz Saeed, It remains always incomplete.
Denial is state of mind in Pakistan. Who ruined Afghanistan? USSR or may be US. Who forced IA to come to Valley and make life hell for Kashmiris? Indians may be, we didn't do it. 9/11 - Israel, 26/11- India, Osama Killed - Was a Lie etc Pakistan have enough share of denial.