It takes as long as the spring only because they weren't looking. They can stretch the oath that far, they can be disinterested in knowing - but now they know, and so there it is. Elwing of Sirion is twenty-three. Half-man, so fully grown. Sirion is a city of refugees. Elves and Men and, since there are Men, children. Elwing herself has infant children.
They debate whether to send messengers. Debating is allowed, even protracted debating. The Oath, these days, is loud in their minds, and louder when they're pushing it like this, but they drag out the debate for a few months. Messengers will probably be shot on sight. The last time Elwing of Sirion received news of the House of Fëanor it would have been the news that her brothers, twins, aged seven, had not survived the sack of Menegroth.
They send messengers anyway. The messengers are shot on sight. They have good armor, Fëanorian armor, and return home injured but not lethally. Maglor's songs no longer stitch them together. War makes you worse at healing. Maglor's songs are more powerful than ever - he can knock back a wave of approaching enemies, he can make a blade's next touch deadly, he can make them faster and more impervious to danger, but he can no longer do healing.
Maedhros, when he thinks about this, thinks that perhaps there needs to be part of you that is not broken for healing spells to draw on. Or perhaps the Enemy is amused to strip that away first. Perhaps the Enemy finds it suited to the theme as the Oath tugs and yanks and twists them into violence against the lands they once defended and the peoples they once sheltered.
They send messengers to Sirion again. The messengers deliver a plea for the Silmaril, an offer of anything at all in exchange. The messengers do not return at all.
The Enemy is many many hundreds of miles from here but at night Maedhros can hear him in his head. Is it so implausible that I really let you go? the Enemy likes saying. You serve me better free than you ever would have willingly.
The Oath allows them to work slowly. They begin planning the sack of the refugee camp even more slowly than the Oath allows, so slowly that its currents are constantly tugging at them. Any slower and the currents would erode all the things they care about which are not the Oath, and it would be a disaster to go to Sirion once they've been stripped of their capacity to care about anything that is not the Silmaril. So they do not hold out forever. But they work as slowly as they can.
And then she hits the tear and she cannot go where she was told and she does not have general permission to fly. She can twitch her wings, which is enough to barely steer her fall. She can't even yell for help - this has to be the mortal world, she won't even be able to fix her last batch of injuries - when she hits the ground it twists her bad knee, jars her wrist when she pitches forward, but she manages with her little freedom of movement not to roll and aggravate any of the cuts and scrapes.
She is crouched still on the ground, breathing, moving her eyes but forbidden to lift her head.
"Go out," he says, because others will be hearing that also, "and find who's left us a present." And ask her to keep the blind horror and anguish quiet - kill her if she wants to die -"never mind that," he says, "I'll go." It is almost certainly a trap and he is not inclined to be cautious with his life, but the Oath disagrees so he goes armored, and cautiously.
Her mind does not stop crying out. As he gets closer he can piece together some things about it.
She's going to be stuck here till Thorn forgets her name, if nobody finds her, or if somebody finds her and she can't convince them to feed her and let her go. And then she supposes she gets to wander the mortal world until she chances upon another tear or an actual gate, and at least finding her continent again will be straightforward unless she takes so long to get back to Fairyland that the Queen's up and moved somewhere in that time. She weighs probabilities. Maybe she shouldn't go back - to the continent, anyway, she doesn't really want to spend the rest of eternity without sorcery. But oh she misses her tree. Thorn did not break her thoroughly enough to feel confident in making her use her tree for his purposes. It is probably still there, he probably didn't burn it down. She will just have to remember where it is and go back to it whenever she can, whenever that is.
unless she takes so long to get back to Fairyland
till Thorn forgets her name
Her head is not a pleasant place to be but it is also a confusing one and he keeps lingering, wondering what kind of game this is, what reaction it is supposed to provoke from him. "Hello," he says.
Twitch. She's not allowed to talk. She can wiggle a wing, make it clear she's not deaf? Wiggle. This is literally just some random mortal and she has no idea what he'll do with her but she can't exactly evaluate people for suitability as rescue masters from here can she.
Of course mortals don't know how this works. She twitches her other wing marginally more energetically. You can't just give random people permission to do things, wouldn't that be nice, every bad court would fall apart as soon as somebody walked by and yelled.
...She can make facial expressions. Does he think she's a mortal? With wings? Do mortals ever have those, she thought they didn't. She twitches the wing now designated for negative answers. No, I don't want you to kill me, or swallow the sun, or time travel, I do not require anything literally impossible of you, you just need to feed me literally anything and say you rescind all my orders -
No because she can't TALK! - If he knew about food and asked someone to fetch some before he came out to find her why is he acting like he doesn't know what's going on? Does he know about fairies or not? Or do mortals come in 'super hearing', or has he got a broadear captive back wherever - no, if he had a broadear he'd know how fairies work -
- and now she's brute forcing cube roots in her head. Do you get 9,805,344,209,101 if you multiply 20,000 by itself three times LET'S FIND OUT
- she cannot actually be permitted to wander around Beleriand, not if the portrait that is coming together is at all accurate. The right thing to do would be to send her to Círdan.
Someone comes running with food.
She has practice at this for some reason.
- what's he going to do with her, he's reading her mind stop stop stop stop -
- she shivers violently, she can do that, it's not volitional, but she opens her mouth. She told Thorn when he asked her that leaving this avenue wide open was a security hole but he kinks on hand feeding so she's allowed to be hand-fed because nothing should ever obstruct Thorn from kinking on things, oh no -
"How can I tell, I need to be able to tell -" Especially if he wants her to think, she's astonished she managed to think as well as she did with Thorn making her talk but then at least she had a moment's warning before any specific privacy evaporated.
Shiver. "Okay. Now that you've fed me I'm your vassal and you're the only person on hand - unless somebody else had a really strong specific claim to that specific piece of food before you gave it to me, maybe - who can rescind or supplement my orders. A lot of them are really uncomfortable and I would like to stop having them now. Please."