WHAT IS THE PROCESS AND COST TO OBTAIN A SMALL ESTATE AFFIDAVIT?

MY PARENTS DIED ON THE SAME DAY (ORDER OF DEATH, MY FATHER THEN MY MOTHER). MY DAD HAD A LIFE INSURANCE POLICY AND LEFT MY MOTHER AND I AS PRIMARY BENEFICIARIES. THE LIFE COMPANY HAS DISBURSED FUNDS TO ME BUT IS HOLDING MY MOTHER'S PORTION UNTIL I CAN PROVIDE THEM WITH A SMALL ESTATE AFFIDAVIT. MY PARENTS LEFT MY SISTER AND I AS SUCCESSOR TRUSTEES OF THEIR TRUST AND WITHIN THE TRUST THEY INCLUDED THEIR WISHES IN A WILL. ALL DOCUMENTS ARE SIGNED BY MY PARENTS WHICH INCLUDE WITNESSES AND NOTARY. I WANT TO AVOID PROBATE BUT THE LIFE INSURANCE COMPANY WILL NOT ACCEPT THE TRUST OR THE WILL, EVEN THOUGH ALL DOCS ARE NOTARIZED.