Fëanor asks it of all of them. Each new soul to walk within the Halls of Mandos is sought out and given his questions. He is brilliant and he is driven, and not knowing is a thing he cannot bear.
Even those who've had no cause to wish him well answer when they see the look in his eyes, the need to know the answer to his questions.
"Where is Macalaurë, also called Maglor? How fares my son?"
Always, they do not know. And always, always, they look to Maedhros as they ask, "Did he not come here with you?"