(a) Upon initiating the probate of an estate, the will of the decedent shall be filed with the court. Such will may be proven and admitted to probate by filing an affidavit of an attesting witness which identifies such will as being the will which the decedent executed and declared to be his or her last will. If the evidence of none of the attesting witnesses is available, the court may allow proof of the will by testimony that the signature of the testator is genuine.

(b) At any time within 90 days after a will has been admitted to probate, any person having an interest in the decedent's estate may contest the validity of such will. In the event of such contest, a hearing shall be held to determine the validity of such will.

(c) Upon considering all relevant information concerning the will, the Court of Indian Offenses shall enter an order affirming the admission of such will to probate, or rejecting such will and ordering that the probate of the decedent's estate proceed as if the decedent had died intestate.