Transfer authorized by will or trust.

A personal representative or trustee may make an irrevocable transfer pursuant to section 21-309 to a custodian for the benefit of a minor as authorized in the governing will or trust, subject to the authority of the court under section 20-1106. If the testator or the settlor has nominated a custodian under section 21-303 to receive the custodial property, the transfer must be made to that person. If the testator or the settlor has not nominated a custodian under section 21-303 or if all persons so nominated die before the transfer or are unable, decline, or are ineligible to serve, the personal representative or the trustee shall designate a custodian from among those eligible to serve as custodian for property of that kind under section 21-309(a).