King Treven of Valdemar rises to speak. He has the public speaking skills of someone tutored in it since childhood.
Valdemar's situation is dire. The occupiers have Arda magic, in the form of Sauron; without any corresponding advantage to combat that, fighting to get their country back will be very difficult. Sauron has tricked Vkandis Sunlord into joining his cause, perhaps corrupted Him entirely. He speaks a little about the atrocities they know have been and are likely still being committed in Valdemar's territory. He speaks of the courage and determination of the Valdemaran people - there are tears in his eyes - and how important it is to him, and the other surviving Heralds, that they somehow bring an end to the horrors.
Sauron wants to bring Melkor back from the Void, by slaughtering half a million people. If this happens, the war is lost - Velgarth is probably lost - perhaps Eru intended Melkor to exist here, in Arda, balanced by the other Valar, but Velgarth is different. Velgarth's gods are unprepared to fight off this invasion alone, or else the war would be won.
Treven knows his Arda history. A long time ago, in the first war with Melkor, Eru saw that the Valar needed help, and granted them another god.
If Velgarth has a creator god, They have never spoken to anyone and do not seem to be watching now or steering events. Only people, and the current gods, are available to do that. Valdemar has an alliance with the Shadowgod of their region, and also the Star-Eyed Goddess. They have said that they can't fight Vkandis-and-Sauron alone; even their ability to communicate with the humans here is limited. They're currently at an impasse. Neither side has the strength to win outright, but if Sauron retrieves Melkor, it's over.
But in Velgarth, mortals can build a god. Albeit at a steep cost.
They have the Shadowgod's approval for this. They have the approval of Mandos, who is working together with the Shadowgod on a plan. The plan will likely involve slaughter, because at this point they have fewer other options. Treven squares his shoulders, looks straight at the Valar, and says that he is certain the people of Valdemar, his nation, would consent to this, if there were any way to ask them. There isn't, since they are currently under the tyranny of Sauron. Mandos will help the Shadow-Lover bring them back. Mandos agrees to do this also for any Quendi who wish to volunteer; Quendi can give more energy with this sacrifice, saving other humans.
...The Silmarils are, in themselves, a power source. Treven isn't sure, yet, how many human lives might be saved by having them, but...many.
He will swear not to return the Silmarils to Arda, where they might be used for destruction there. The Valar can enforce this. But he pleads for his people to be allowed to accept this generous gift from the King of the Noldor, their allies, which might end up turning the tide of the war.