Question: Can a player who has been disqualified still declare another player’s hand dead?

Answer: No, a disqualified player cannot declare another player’s hand dead. Once a player’s hand has been declared dead, they are no longer permitted to make any decisions or calls regarding other player’s hands. A disqualified player must remain silent for the remainder of the game after their hand has been declared dead.

Source: Mah Jongg Made Easy 2024,  page 31 para. 6