Force to complete 90 days of notice Period in IT company

Hello, I have submitted my resignation on 13th Feb. I requested for an early release with Last working day as March 13th. I will be serving 1 month out of 3 months of notice period. For the shortfall of 2 months, I am willing to pay. I am moving to Canada for personal health and career reasons. I need to join my new employer in Canada on March 20th. My tickets are booked for March 17th. I explained my reasons to my manager. Manager is ok to release me , however his boss(my superboss) isn't accepting early release. Manager can't give approval until his boss approves. HR is ok to release upon Manager's approval. Tried pleading the super boss , but he says its his policy he can't relieve though I don't have any dependencies. He is asking to abscond when I asked for a solution. Please advise.. Kindly refer the policy before. Thanks in advance! As per the policy provided in my appointment letter "In the event of your resignation or termination of services, either side will have to give a notice of 90 Days or payment of 90 Days gross salary in lieu of such notice. In the event of resignation, your dues and final settlement would be credited to your bank account held for ABC Salary on the last working day of the following month along with payroll. If you have any Annual Leave balance, it will be encased in the settlement. During your employment with the Company, your terms of employment will be governed by the policies and rules of the Company framed from time to time. These rules will cover Provident Fund, Leave Travel Assistance, Medical, Indiscipline, Misconduct or any other matter pertaining to company policies and rules. Note: The above terms and conditions are subject to Company’s Policy. All other terms and conditions of your employment will be governed by the employment policy of the company being in force at the relevant period."