(a) If a contest is filed before the official result of the contested election is determined, the contestant may name as contestee the person shown by the election returns at the time of filing to be the appropriate contestee as determined under Subtitle B or C.
(b) If the final canvass reveals that a necessary contestee as determined under Subtitle B or C has not been named, the contestant must name that contestee within the time limit prescribed for filing the petition. Action taken before the necessary contestee is named shall be set aside if it denies to the contestee any right to which a contestee is entitled.