Maitimo makes no particular arrangements to speak with him, and that hurts.
There are guards outside the door. He can ask the guards to take him places, if he wants, so it's not exactly confinement, but it halfway is and so it'll halfway kill him after long enough. It's causing irritability already.
...technically, it is possible that he is irritated because Maitimo, who once he loved, who once he trusted, murdered his parents in the middle of the night and has not bothered to speak to him since, not for a week. That is the kind of thing that he can imagine causing irritation even in someone who isn't under house arrest and starting to itch under their skin from the not-quite-confinement.
He tries to think through what Maitimo should have done instead. Come and apologized? He is inclined to think he would spit in his face but it's Maitimo, probably it wouldn't have gone like that, probably that conversation would have wound its way through all of the thousand minefields in front of it and ended with forgiveness. Maybe Maitimo hasn't come to talk to him in order to spare him that.
Had him murdered too? It would have the advantage that he'd have less to explain to his father, and that he wouldn't be pacing this room in anxious anticipation that at any moment a civil war could break out and the guards at the door fall to hunting arrows and friends of his come gleefully to his rescue, handing him a weapon he could turn against Maitimo in the pursuit of his rightful vengeance.
No, probably Maitimo's avoiding that somehow. It'd be unlike Maitimo to let that happen. If Maitimo thought he were a dangerous inspiration to his people he'd be dead, that's all there was to that. He was here only because it didn't matter and since it didn't matter Maitimo preferred him alive.
But not so they could talk.
Maitimo sends him a statement to climb the tower and read. It says that he is horrified that Melkor's machinations stirred so many to treason against their rightful King and their own family, and that this cannot be permitted to happen again. It says that Melkor would only have gone to such lengths to divide the Noldor if he knew that, united, they would destroy him. It says that only the decisive action of the King against traitors stopped this scheme in its tracks, and that for this all the Noldor must be grateful. It says that he swears his King his allegiance.
"I want to talk with him."
"You want to talk with who?"
"I want to talk with the King."
"The King had a second message for if you asked to talk to him, do you want me to read it?"
"I - yes."
"Nolofinwion, I am grateful you appreciate the necessity of a united front. Your cooperation in this matter ensures the safety of your sister and brothers, who it would grieve me greatly to lose to Mandos."
"He said," Findekáno says, "to read that if I asked to talk to him?"
"That's crueller than just saying it in the first place."
"You shouldn't criticize the King," says the guard.
"I'm trying to understand."
"I don't think he's making himself very difficult to understand."
He climbs the tower and reads the statement.
By the end of the week he has a headache and his limbs sometimes shake involuntarily. "We're heading to Alqualondë," one of the guards says.
"I want to see my cousin."
"Your cousins will be required to remain here in Tirion." His full-cousins, she means, of course - Findaráto and Artanis and Angaráto and Aikanáro.
"Ah," he says. "I'm coming with, though?"
"The King doesn't think you're a traitor." She sounds a touch skeptical.
"I'm not." Nor were his full-cousins, so that couldn't have much to do with it. "I want to see the King my cousin."
"I assume that if it's worth his time to talk to you, he will."
He doesn't. He secures them boats in Alqualondë, somehow. Findekáno hears it rumored that in exchange his full-cousins are now safe. They cross the sea and the guards outside his door are called away to join a fight and he opens his door, contemplates walking a few hundred feet, decides not to. He sits right outside his door so that the headache eases, and he sings.
Two weeks later the guards are back.
"Did we win?"
"Are people dead?"
She blinks at him disbelievingly. "Thousands of them."
"Can I - the names -"
"Maybe later. The King wants you."