(a) A qualified expert witness must be qualified to testify regarding whether the child's continued custody by the parent or Indian custodian is likely to result in serious emotional or physical damage to the child and should be qualified to testify as to the prevailing social and cultural standards of the Indian child's Tribe. A person may be designated by the Indian child's Tribe as being qualified to testify to the prevailing social and cultural standards of the Indian child's Tribe.
(b) The court or any party may request the assistance of the Indian child's Tribe or the BIA office serving the Indian child's Tribe in locating persons qualified to serve as expert witnesses.
(c) The social worker regularly assigned to the Indian child may not serve as a qualified expert witness in child-custody proceedings concerning the child.