Does EPF operate outside the Will ?

Yes, it does. Under the Employees Provident Fund (EPF) Act, you may nominate where your money goes upon your death. So if you have made a nomination under the EPF Act, your nominee(s) will be entitled to the fund in your EPF Account, regardless of what your Will states.

If you have not made a nomination, your EPF fund will be distributed according to your Will, if any, or according to the intestacy laws.

Marriage revokes a nomination. So if you get married after making a nomination, it is automatically cancelled. Make a new nomination after your marriage.